In verse 62 of Suratul Ahzab, the Qur’an mentions that one of the unchanging 'courses of Allah' is 'exterminating the conspirators (against Islam) by means of one general attack - the like of which have been observed in the former nations too'.
Similar expressions have also appeared on other occasions in the Qur’an.
In verse 38 of Suratul Ahzab, the Noble Qur’an, after issuing the permission to break the incorrect pagan custom, which prohibited a person from marrying the divorced wife of his adopted son, says:
سُنَّةَ اللٌّهِ فِي الَّذِينَ خَلَوْا مِنْ قَبْلُ وَ كَانَ أَمْرُ اللٌّهِ قَدَراً مَقْدُوراً
“Such has been the course of Allah (s.w.t.) with respect to those who have gone before; and the command of Allah (s.w.t.) s a decree that is made absolute.”
In verse 43 of Suratul Fatir, after threatening the sinning nations with perdition, the Noble Qur’an says:
فَهَلْ يَنْظُرُونَ إِلاَّ سُنَّةَ الأََوَّلِينَ فَلَنْ تَجِدَ لِسُنَّةِ اللٌّهِ تَبْدِيلاً وَ لَنْ تَجِدَ لِسُنَّةِ اللٌّهِ تَحْوِيلاً
“Then should they wait for aught except the way of the former people? For you shall not find any alteration in the course of Allah; and you shall not find any change in the course of Allah.”
In Suratul Ghafir, verse 85, after asserting that bringing faith after witnessing the annihilating chastisement descending upon them was not at all helpful for the obstinate disbelievers of the past nations, the Qur’an adds:
سُنَّةَ اللٌّهِ الَّتِي قَدْ خَلَتْ فِي عِبَادِهِ وَ خَسِرَ هُنَالِكَ الْكَافِرُونَ
“But their belief was not going to profit them when they had seen Our punishment; (this is) Allah's law, which has indeed obtained in the matter of His servants, and there the unbelievers are lost.”
In verse 23 of Suratul Fath, after speaking about the victory for the believers, defeat for the disbelievers and non-existence of any protector or helper for them in the battles, it adds:
سُنَّةَ اللٌّهِ الَّتِي قَدْ خَلَتْ مِنْ قَبْلُ وَ لَنْ تَجِدَ لِسُنَّةِ اللٌّهِ تَبْدِيلاً
“Such has been the course of Allah (s.w.t.) that has indeed run before, and you shall not find a change in Allah's course.”
And again in verse 77 of Suratul Isra', when speaking of the conspiracy to either banish or kill the Noble Prophet (S), it adds:
سُنَّةَ مَنْ قَدْ أَرْسَلْنَا قَبْلَكَ مِنْ رُسُلِنَا وَ لاَ تَجِدُ لِسُنَّتِنَا تَحْوِيلاً
“(This is Our) course with regard to those of Our messengers whom We sent before you, and you shall not find a change in Our course.”
From all these verses, it can be clearly inferred that ( سنة or سنَنت) courses, in these instances, refer to the fundamental laws related to creation and legislation which are never subject to any alteration. In other words, in the world of divine creation and legislation, Allah (s.w.t.) has ordained certain principles which, similar to the constitutions prevailing amongst the people of the world, cannot become victims of distortion and alteration. These rules had prevailed over the past nations and shall continue to do so over the present and future ones.
Assistance to the prophets, defeat of the disbelievers, the compulsion to act in compliance with the Divine commands howsoever displeasing they may appear to a society, futility of repentance at the time of descent of Divine chastisement and the like are some examples of these eternal courses.1