One of the questions which is often asked about the event of Karbala and Imam al-Husayn (as) is why Allah did not help Imam al-Husayn (as)? Allah is capable of doing whatever He wishes. Why then did Imam al-Husayn (as) not resort to miraculous and supernatural powers in order to repel and exterminate his enemies?
Did Allah not, according to explicit Qur’anic texts, help His Prophet (S) with invisible aid in the Battle of Badr and other wars? Why did the event of Karbala have to end with the martyrdom of Imam al-Husayn (as), all his companions and some members of his family and the captivity of those who remained alive?

The concept of help in Islamic thought

The concept of help [nusrat] enjoys a special position in Islamic thought, and the Holy Qur’an has mentioned a number of instances in this regard.

A. The means of Allah’s help

Some verses of the Holy Qur’an have recounted the means of Allah’s help, such as:

1. Eradicating the unjust

The Holy Qur’an mentions eradicating and uprooting the unjust, an action that is in reality a kind of help to the monotheists and believers. Allah, the Exalted, says,

    ﴿ قَالَ رَبَّ انْصُرْنِي بِمَا کَذَّبُونِ * قَالَ عَمَّا قَلِيلٍ لَيُصْبِحُنَّ نَادِمِينَ * فَأَخَذَتْهُمُ الصَّيْحَةُ بِالحَقِّ فَجَعَلْنَاهُمْ غُثَاءاً فَبُعْداً لِلْقَوْمٍ الظَّالِمِينَ * ثُمَّ أَنشَأنَا مِنْ بَعْدِهِمْ قَرُوناً آخِرِين ﴾

“He said: O my Lord! Help me against their calling me a liar. He said: In a little while they will most certainly be repenting. So the punishment overtook them in justice, and We made them as rubbish; so away with the unjust people. Then we raised after them other generations.”1

2. Invisible soldiers

Sometimes Allah helps believers with invisible soldiers; meaning that He helps believers by means of the angels.
Allah the Most High says,

    ﴿ إِلاّ تَنْصُرُوهُ فَقَدْ نَصَرَهُ اللهُ إِذ أَخْرَجَهُ الَّذِينَ کَفَرُوا ثَانِي اثْنَيْنِ إِذْهُمَا فِي الْغَارِ إِذْ يقُولُ لِصَاحِبِهِ لا تَحْزَنْ إِنَّ اللهَ مَعَنَا فَأَنْزَلَ اللهُ سَکينَتَهُ عَلَيْهِ وَأَيَّدَهُ بِجُنُودٍ لَمْ تَرَوْهَا وَجَعَلَ کَلِمَةَ الَّذِينَ کَفَرُوا السُّفْلي وَکَلِمَة اللهِ هِي الْعُلْيا وَاللهُ عَزِيزُ حِکِيمٌ ﴾
 

“If you will not aid him, Allah certainly aided him when those who disbelieved expelled him, he being the second of the two, when they were both in the cave, when he said to his companion: Grieve not, surely Allah is with us. So Allah sent down His tranquillity upon him and strengthened him with hosts which you did not see, and made lowest the word of those who disbelieved; and the word of Allah, that is the highest; and Allah is Mighty, Wise.”2

3. Intimidation and fear

Sometimes, the fear that Allah puts in the hearts of the unbelievers is a kind of help to the believers. By this means, Allah intimidates the unbelievers. Allah says,

    ﴿ سَنُلْقِي فِي قُلُوبِ الَّذِينَ کَفَرُوا الرُّعْبَ بِمَا أَشْرَکُوا بِاللهِ مَا لَمْ ينَزِّلْ بِهِ سُلْطَاناً وَمَأْوَاهُمُ النَّارُ وَبِئْسَ مَثْوَي الظَّالِمِينَ ﴾
 

“We will cast terror into the hearts of those who disbelieve, because they set up for Allah that which He has sent down no authority, and their abode is the fire; and evil is the abode of the unjust.”3
Intimidation and fear are the most effective weapons on the battlefield, and Allah has helped the believers enjoy the benefits of this weapon.

B. The conditions for help

Allah’s help and aid has conditions, which have been mentioned in the verses of the Holy Qur’an; among them:

1. Patience and steadfastness

Allah says,

    ﴿ وَلَنْ تَرْضَي عَنْکَ الْيَهُودُ وَلاَ النَّصَارَي حَتَّی تَتَّبِعَ مِلَّتَهُمْ قُلْ إِنَّ هُدَی اللهِ هُوَ الهُدَی وَلَئِنِ اتَّبَعْتَ أَهْوَائَهُمْ بَعْدَ الَّذِي جَاءَکَ مِنَ الْعِلمِ مَا لَکَ مِنَ اللهِ مِنْ وَلِيٍ وَلا نَصِيرٍ ﴾
 

“And the Jews will not be pleased with you, nor the Christians until you follow their religion. Say: Surely Allah’s guidance is the true guidance. And if you follow their desires after the knowledge that has come to you, you shall have no guardian from Allah, nor any helper.”4
He also says,

    ﴿ أَمْ حَسِبْتُمْ أَنْ تَدْخُلُوا الجَنَّةَ وَلَمِّا يَأْتِکُمْ مَثَلُ الَّذِينَ خَلَوْا مِنْ قَبْلِکُمْ مَسَّتْهُمُ الْبَأْسَاءُ وَالضَّرَّاءُ وَزُلْزِلُوا حَتَّى يَقُولَ الرَّسُولُ وَالَّذِينَ آمَنُوا مَعَهُ مَـتَى نَصْرُ اللهِ أَلاَ إِنَّ نَصْرَ اللهِ قَرِيبٌ ﴾
 

“Or do you think that you would enter the Garden while yet the state of those who have passed away before you has not come upon you, distress and affliction befell them and they were shaken violently, so that the Apostle and those who believed with him said: When will the help of Allah come? Now surely the help of Allah is nigh!”5

2. Preserving and safeguarding help

One of the conditions for receiving Allah’s help is that the people for whom this help is meant should possess the capacity and worthiness to receive that help, meaning that they should preserve it and bring about social justice after the fulfilment of Allah’s help.
Allah, the Exalted, says,

    ﴿ اُذِنَ لِلَّذِينَ يُقَاتَلُونَ بِأَنَّهُمْ ظُلِمُوا وَإِنَّ اللهَ عَلَي نَصْرِهِم لَقَدِيرٌ * الَّذينَ اُخْرِجُوا مِنْ دِيارِهِمْ بِغَيْرِ حَقٍّ إِلاَّ أَنْ يقُولُوا رَبُّنَا اللهُ وَلَو لا دَفْعُ اللهِ النَّاسَ بَعْضَهُمْ بِبَعْضٍ لَهُدِّمَتْ صَوَامِعُ وَبِيَعٌ وَصَلَوَاتٌ وَمَسَاجِدُ يُذْکَرُ فِيهَا اسْمُ اللهِ کَثيراً وَلَينْصُرَنَّ اللهُ مَنْ يَنْصُرُهُ إِنَّ اللهَ لَقَوِيٌ عَزِيزٌ * أَلَّذِينَ إِنْ مَکَّنَّاهُمْ فِي الأَرْضِ أَقَامُوا الصَّلاَةَ وءاتَوُا الزَّکَاةَ وَأَمَرُوا بِالمَعْرُوفِ وَنَهَوْا عَنِ المُنْکَرِ وَللهِ عَاقِبَةُ الاُمُورِ ﴾
 

“Permission to fight is given to those upon whom war is made because they are oppressed, and most surely Allah is well able to assist them; those who have been expelled from their homes without a just cause except that they say: Our Lord is Allah. And had there not been Allah’s repelling some people with others, certainly there would have been pulled down cloisters and churches and synagogues and mosques in which Allah’s name is much remembered; and surely Allah will help him who helps His cause; most surely Allah is Strong, Mighty. Those who, should We establish them in the land, will keep prayer and pay the poor rate and enjoin good and forbid evil; and Allah’s is the end of affairs.”6

C. Testing a believer by withholding help

It can be inferred from certain verses of the Holy Qur’an that sometimes Allah tests the believers by withholding help from them. He intends to manifest whether they have perseverance and firmness of purpose or are weak and fainthearted. Will they run away from the battlefield or stand firmly defending the religion of Allah? Allah, the Exalted says,

    ﴿ وَلا تَهِنُوا وَلا تَحْزَنُوا وَأَنتُمُ الأَعْلُونَ إِنْ کُنْتُمْ مُؤْمِنِينَ * إِنْ يمْسَسْکُمْ قَرْحٌ فَقَدْ مَسَّ الْقَوْمَ قَرْحٌ مِثْلُهُ وَتِلْکَ الأَيَّامُ نُداوِلُها بَيْنَ النَّاسِ وَلِيَعْلَمَ اللهُ الَّذِينَ آمَنُوا وَيتـَّخِذَ مِنْکُم شُهَدَاءَ وَاللهُ لا يُحِبُّ الظَّالِمِينَ * وَلِيُمَحِّصَ اللهُ الَّذِينَ آمَنُوا وَيَمْحَقَ الْکَافِرِينَ * أَمْ حَسِبْتُمْ أَنْ تَدْخُلُوا الجَنَّةَ وَلَمَّا يَعْلَمِ اللهُ الَّذِينَ جَاهَدُوا مِنْکُمْ وَيَعْلَمَ الصَّابِرِينَ ﴾
 

“And be not infirm, and be not grieving, and you shall have the upper hand if you are believers. If a wound has afflicted you (at the Battle of Uhud), a wound like it has also afflicted the unbelieving people; and We bring these days to men by turns, and that Allah may know those who believe and take witnesses from among you; and Allah does not love the unjust. And that He may purge those who believe and deprive the unbelievers of blessings. Do you think that you will enter the Garden while Allah has not yet known those who strive hard from among you, and (He has not) known the patient.”7

Responses to two questions

Sometimes it is asked whether or not Imam al-Husayn (as) achieved the professed objectives of his movement. Also, the question is sometimes asked as to whether Imam al-Husayn (as) was militarily victorious over his enemies or not. Here, what is meant by victory is a victory which leads to rule and government.
The answer to the first question is that Imam al-Husayn (as) certainly attained to the professed aims and objectives of his uprising and undoubtedly came out of the war victorious as shown in previous discussion.
As for the second question, it must be said that the answer is negative; because outwardly the army of ‘Umar ibn Sa‘d managed to prevail over the tiny army of Imam al-Husayn (as), killing Imam al-Husayn himself (as), the youths of Bani Hashim and many of his companions. This is something which, from a military perspective, apparently looks like defeat.
However, Imam al-Husayn’s (as) uprising had aims and objectives beyond military defeat and governmental rule. The Imam intended to awaken the Islamic community; a community that had sunk into apathy and indifference, and had turned the teachings of Islam upside down. The only factor that could awaken the consciences of these insensible people from their deep sleep of negligence was Imam al-Husayn’s martyrdom.
That is why we see that after the martyrdom of Imam al-Husayn (as), uprisings sprang up against the rule of Bani Umayyah which finally led to the downfall of this cursed sultanate. It is for this reason that the Holy Prophet (S) said,

    «حسين منّي وأنا من حسين.»

“Al-Husayn is from me, and I am from al-Husayn.”
That is to say that the Holy Prophet (S) and his message is intricately connected to Imam al-Husayn (as) and his uprising.

The triangle of prosperity, trial and free will

Man attains advancement and success by means of trials and difficulties and the use of his free will to make correct decisions about his life. Therefore, prosperity and salvation have no meaning and become worthless when they are attained without trials and self-determination.
In the same way, a man who has never been tempered by trials and afflictions will not put in the same effort to improve and advance and so will never achieve success at the level of his innate and inherent propensity.
Trials are sometimes personal and private and they are sometimes social, including under their fold all aspects of the society. Sickness, poverty, disbelief, children, worldly life, help, opportunity to escape from the battlefield, and other things like this are all kinds of trials for a believing person. Mention has been made in the Holy Qur’an about trials and temptations for believers, when it says,

    وَلَنَبْلَُوَنَّکُمْ حَتَّى نَعْلَمَ المُجَاهِدِينَ مِنْکُم وَالصَّابِرينَ ...
 

“And most certainly, We will try you until We have known those among you who exert themselves hard, and the patient, and made your case manifest.”8

The event of Karbala was a trial for the Muslim ummah

The event of Karbala was a scene of great trial for the Islamic ummah in the same way that the wars which occurred during Imam ‘Ali’s caliphate and the peace which Imam al-Hasan al-Mujtaba (as) made with Mu‘awiyah ibn Abu Sufiyan were all incidents of Allah’s trials for the Islamic community.
Allah tried the Muslims to manifest who in reality was trudging the path of truth and justice and would follow the Infallible Imams (as) from those who had deviated from the path of the Ahl al-Bayt (as). In this way, everyone was made known by his own actions.
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Reference
    1. Surat al-Mu’minun 23:39-42.
    2. Surat al-Tawbah (or Bara’ah) 9:40.
    3. Surat Al ‘Imran 3:151.
    4. Surat al-Baqarah 2:120.
    5. Surat al-Baqarah 2:214.
    6. Surat al-Hajj 22:39-41.
    7. Surat Al ‘Imran 3:139-142.
    8. Surat Muhammad 47:31.