From the first, Islam has said that it is the last message, and Muslims have accepted this fact with wisdom and with love, and have realized that Islam is the last manifestation of revelation, prophet hood and the culmination o I the former pure religions.
Also, all Muslims, on the basis of ayahs in the Qur'an and hadith, believe that the Prophet of Is lam (S.A.) is the last Messenger of Allah who was the recipient of human leadership.
The great Qur'an has explained the universality of the pure religion of Islam in many ayahs and has shown that Muhammad (S.A.) is the last emissary sent by God: "Muhammad is not the father of any of one of your men, but the Messenger of Allah and the Seal of the Prophets; and Allah has knowledge of everything." (XXXIH, ~4O)
It has been said in a hadith from the Prophet (S.A) to 'Ali (A.S): "In all respects your relation to me is like that of Harun to Musa (i.e. if Harun was Musa's brother, I also take you as a brother according to the rules of brotherhood; if he was Musa's successor, you also will be my successor). Except that Musa was not the last prophet, and I am the last"
He also said: "I am the last brick in the building of prophet hood. With my coming the prophets have come to an end."
Imam 'Ali (A.S.) said in Nahj al-Balaghah, the great book of learning and knowledge: "With the Prophet of Islam, Muhammad (S.A.), revelation came to an end." (Sermon 133)
The eighth leader, the true Imam, Hazrat Rida (A.S.) said: 'The pure religion of Muhammad (S.A.) will not be abrogated till the Day of Resurrection, and also no prophet will follow him.' (Bihar al-Anwar, vol. II, p. 34)
It is an authentic hadith accepted by both the Shi'a and the Sunnis, see aI-Ghadir, vol. 3. p. 196-202.
What we have just recounted is only a sample of tens of hadiths, which clearly and succinctly explain the conclusive status of the Prophet (S.A.) and the perpetuity of his pure religion; they leave no room for doubt.

The Universality of Islam
One of the greatest causes of Islam's ever-lastingness is its 'all-inclusiveness'.
Islam is a comprehensive project based on the human disposition, and it embraces all aspects of life: individual, social, material, spiritual, doctrinal,emotional, economic, legal and so forth, and it explains the basis of each in the most acceptable way, most realistically, for all peoples and all levels of people, in every time and place.
Thus European Islamic scholars, each with his deep view and research, have all acknowledged the omni-sidedness of Islamic laws and its universality. Now let us investigate some aspects of this universality.

The God of Islam and the Qur'an.
The God of Islam is the Preserver of all worldly things. He is not the god of a tribe, for some special group only. At prayer we say: 'al-hamdu li'llahi rabbi'l-alamin ''Praise be to Allah, the Lord of the worlds.'
Every moment, in every place, whenever He wants, He brings into existence; there is no limitation on His Essence. He has authority over all existent things.
"Blessed be He in whose hand is the Kingdom. He is Powerful over everything.' (LXVII1)
He is aware of the manifest and the concealed, the past and the future, and everything, even what is in our hearts?
'He knoweth whatever is in the heavens and the earth, and-He knoweth whatever you conceal and whatever you declare, and Allah knoweth whatever is In the breasts.' (LXI; 4)
Being with Hun is possible in every place: there is no need to travel or to pass by a doorman. He is nearer to us than anything.
"We are nearer to him (man) than his jugular vein' (L; 16)
He is a reality without parallel, beyond all human attributes and likenesses; He is not like the gods of other altered religions who have become man-like or like something created. Therefore He has no place. For He created place.
He is not contained in time, for He is the creator of time. He is not associated, nor has He any beginning or ending. Therefore, He has no like or similitude.
"Like him there is naught; He is the All-hearing the All seeing." (XLII; 1 1)
His Essence is beyond sleep, tiredness, remorse and so forth. "Slumber seizes him not, neither sleep." (II; 255) "Say: He is Allah, One." (CXII;I)
He is one without equal: He has no son or mother or father, neither partner nor associate. This is the reality in Surah Tawhid, which Muslims recite many times each day in prayer so as to be far from the possibility of associating something with Him (shirk).
The God of Islam is a God with all the attributes assigned to by the pure, sweet tongue of the Qur'an, with an understanding wider, more magnificent, greater than can be conceived by created intelligences. Free from want, without partner, prevailing, close, supreme, compassionate, most compassionate, available to all so that anyone at any time may communicate with Him, bring his needs before Him, ask whatever he wishes of Him, that He may make available what is of benefit and what is expedient, as He Himself said: 'And verily, Allah is to you All-gentle, All-compassionate.' (LVII; 9)

The Equality of All in Islam
Superiority of race or segregation is not only eliminated and void in the eyes of Islam, but the equality of man is an absolute reality from the point of view of Islam, and it says that all men are equal, all are from one father and one mother and are members of one family, and from the aspect of nobility, origin and connections they are equal partners. No one is better than anyone else, except in purity and devoutness.
"O mankind, we have created you male and female and appointed you races and tribes that you may know one another. Surely the noblest among you in the sight of Allah is the most god fearing of you; Allah is All-knowing All-aware.' (XLIX; 13)

Islam and Freedom of Thought
Islam is a firm supporter of logic, rational argument and freedom of thought. Imposition of ideas or beliefs, or the stifling of voices does not exist in Islam.
No compulsion is there in religion. Rectitude has become clear from error. (Th256)
beliefs is a duty for every individual, and it is an obligation for everyone not to accept anything without proof, and if some commands and precepts are obligatory and must be accepted without why and wherefore, it is because they are from the source of revelation which cannot be in error, and because they have been stated through the Prophet and the pure Imams.
Islam censures those who blindly follow the beliefs of their fathers and ancestors, and commends self-investigation and deep examination. It rejects feeble-mindedness and vain speculation, and urges only to the perusal of knowledge and certainty.
And pursue not that thou hart no knowledge of; the hearing the sight~ the heart - all of these shall be questioned of (XVH, ~36)
Islam grants its opponents the right to set forth their queries in reasonable discussion and to enumerate their proofs and listen to the answers.
Say: 'Produce your proof if you speak truly.' (H111)
This was the reason that many Jews, Christians and those from other groups who took a stand against Islam, came to the Prophet or the pure Imams, and sat down and discussed their religious ideas.

Islam and the Invitation to Thought and Education
Islam lends great value to thinking, it asks the learned and wise to think and think again about creation, time, night and day, the sky, the earth, animal life, man and the universe and what is in it.
Surely in the creation of the heavens and the earth and the alternation of night and day, and the ship that runs in the sea with profit to men, and the water Allah sends down from the sky therewith reviving the earth after it is dead, and His scattering abroad in it all manner of crawling thing, and the turning about of the winds and the clouds compelled between heaven and earth, surely there are signs for a people having understanding. (Ii, ~164)
Also it asks them to research into the lives of those who came before, their thoughts and the causes of their decline and fall, so that they may keep far from the precipices of their destruction.
Divers institutions have passed away before you; journey in the land and behold how was the end of those that cried lies. This is an exposition of mankind, and a guidance and an admonition for the God fearing. (III; 136-7)
In short, Islam desires that man should think deeply and freely and travel across the far horizons of thought and knowledge and take everything that is best for the improvement of his being.
For this reason Islam values scientific advances and discoveries which are for the help of humanity, and this is why scientists and scholars rose up in the centuries following the advent of Islam, to decorate the high road of human civilization with the jewel' of their scientific endeavors, so much so those there great names will shine forever at the summit of scientific history. They include Jabir ibn Hayyan, Razi, Ibn Sina (Avicenna) and Khwajah Nasir ad-Din Tusi, who were celebrated in all the sciences of their times: the intellectual sciences, natural science, astronomy, Chemistry, etc. The books of Ibn Sina were even being taught in European universities up to the end of the last century. Jurji Zaydan, the famous Christian Lebanese writer, says on page 598 of his History of Islamic Civilization: "As soon as Islamic civilization found its feet, and the new sciences spread among the Muslims, Muslim scholars appeared whose thinking was more important than the founders of some of the branches of the sciences. In fact these sciences took on a fresh colour with the new researches of Islamic scientists, and progressed due to Islamic civilization."

Islam's Life-Concept
From the view of Islam, there is no opposition between the material and the spiritual life, the world and religion. Similarly, those who do not work in this world or make no effort are not approved of, although those who do not think of anything apart from individual benefit and consumption and profit are also detested from the point of view of Islam.
Imam Sadiq (A.S.), the sixth Imam, said: "He who abandons this world for the next - i.e. he who withdraws from the activities of life in the name of asceticism - and he who gives up the next world for this world, both are not from among us." (Wasa'il ash-Shi'a, vol. 12, p. 49).
So it can be said that in this matter Muslims should adjust their actions with equal movement in this world, advancing with its happiness, and in the spiritual world. Therefore in Islam there is no monasticism, being a burden on society, social withdrawal, egoism or seclusion. The Prophet (S.A.) said: "There is no monasticism for us; the monasticism for my followers is jihad in the way of Allah." (Bihar al-Anwar, vol 70, p. 114).

Islamic Commands and the Advance of Time
The transformation, evolution and development of the means of living and progress in the various elements of civilization have no kind of incompatibility with the eternity of the commands of Islam, because the incompatibility of a law with this kind of progress is because the law depends on fundamental means and special factors. For example, if one makes a law: Only the hand must be used when writing, only a donkey must be used for travel, etc., this kind of law cannot come into action when science and civilisation advance.
But if it is not in contradiction with fundamental means, and at the time of making the law these were only used as examples, they will not clash with the occurrence of new means and the advance of civilisation.
Islamic laws are of this latter category, that is to say they do not look especially at the means of one period in history. For example, they say: One must be unconquerable with regard to foreign powers so as to defend one's vital and human rights. This law, although it was declared in the time of the sword, never depends on the instruments of that time, i.e. Islam never says: The Islamic jihad must only be with swords. Thus it is practicable today. Similarly with business transactions, trade, work, etc.
So, however much civilization and its means and elements expand, it will never leave the domain of inclusion in the laws of Islam, and this is one of the secrets of the eternity of Islam.
Does Islam Dispense with Contemporary Ideologies and Systems of Thought?
There is no doubt that man has progressed far in the way of knowledge, but scientists themselves confess that what they know in the world of creation is not comparable with what they do not know. And basically, since their vision is limited, they cannot find out all the secrets of the world.
Moreover, each leap forward that man makes is not immune from error. Therefore, in the area of human aspirations, not everything that comes forward, in every field, can be one hundred percent imbued with certainty, because it is possible that environmental factors and other unforeseen things have an effect on man's thinking and outlook and take him far from reality.
But the fundamental project of Islam, since it grows from the root of revelation, has nothing to do with the possibility of mistake, and can give trustworthy guidance at all times of course, with the condition that these pure laws are not inserted within the framework of other deviated systems, whereupon they become completely incapable of deriving advantage.

The Continuation of Divine Assistance
Some imagine that the meaning of the conclusive nature of the Prophet's mission is that after him connection with the hidden, divine world has been interrupted and stopped. This is not valid because the meaning of its conclusiveness is only that after the Prophet of Islam (S.A.), no other prophet or religion will come, not that in a general way connections with the unseen world are also severed.
For with the understanding of Shi'a Muslims, whereby we believe in the Imamate and Wilayat of the twelve pure Imams, this connection is everlasting and is continued by means of these pure ones. And this is one of the distinctive points of the Shi'a school. Mulla Sadra has written in Mafatih al-Ghayb - Keys of the Unseen -"Revelation, that is to say the descent of the angel to the delegated and prophetic eyes, has been forever cut off, but the door of inspiration and illumination has not and will never be closed, and it is not possible for it to be interrupted."

How can Islam be practiced in the Present Day and Age?
Today, and although as time rolls on it becomes greater, and in the end more destructive and more annihilating, we must remember that generosity and magnanimity are found in difficulty. So our independence and individuality demand that we struggle with the aberrations of the times.
Basically, control and reform of the environment can be considered as one of the most pressing duties. The prophets have also taught us by their lives the lesson of the struggle against the aberrations of the times. They never followed the perverse desires of the pulsation of their own societies or the various passions of the environment; eventually they made the environment their own environment.
The Prophet of Islam (S.A.) struggled constantly against the aberrant and amoral customs of the ignorance of his time, 1111 he built another society and environment.
Class differences, the inferiority of women, idol-worship, tribal wars, and tens of other kinds of amorality were among the conventions and customs and beliefs of the people of those days, but the courage of the prophet saw that all of them were destroyed.
Some of the chiefs of the Quraysh, such as 'Utbah, were very unhappy about the Prophet's method, so they arranged a meeting and after they conferred together with him to make him deviate from his way by promise and threat, the Prophet replied to them: "This is what I was delegated to do. I swear by Allah that even if the sun were put in one of my hands and the moon in the other I would not deviate from my way, nor give up my faith, till victory or death ensue."
So let us follow the way of the iron-willed leader and envoy of Allah.