If then any one transgresses the prohibition against you, Transgress ye likewise against him. (Part 1)

If then any one transgresses the prohibition against you, Transgress ye likewise against him. (Part 1)
-Holy Quran.

“They ask thee concerning fighting in the Prohibited Month. Say: "Fighting therein is a grave (offence); but graver is it in the sight of Allah to prevent access to the path of Allah, to deny Him, to prevent access to the Sacred Mosque, and drive out its members." Tumult and oppression are worse than slaughter. Nor will they cease fighting you until they turn you back from your faith if they can. And if any of you Turn back from their faith and die in unbelief, their works will bear no fruit in this life and in the Hereafter; they will be companions of the Fire and will abide therein.”
[Surah Al Baqarah 2:217 ]

The intolerance and persecution of the Pagan clique at Makkah caused untold hardships to the Holy Messenger of Islam and his early disciples. They bore all with meekness and long-suffering patience until the Holy One permitted them to take up arms in self-defence. Then they were twitted with breach of the custom about Prohibited Months, though they were driven to fight during that period against their own feeling in self defence. But their enemies not only forced them to engage in actual warfare, but interfered with their conscience, persecuted them and their families, openly insulted and denied ALLAH (Subhana Wa Ta' la), kept out the Muslims from the Sacred Mosque, and exiled them. Such violence and intolerance are deservedly called worse than slaughter.

“The prohibited month for the prohibited month,- and so for all things prohibited,- there is the law of equality. If then any one transgresses the prohibition against you, Transgress ye likewise against him. But fear Allah, and know that Allah is with those who restrain themselves.”
[Surah Al Baqarah 2:194]

‪#‎Haram‬ = prohibited, sacred. The month of Pilgrimage (Dhu al Hajja)was a sacred month, in which warfare was prohibited by Arab custom. The month preceding (Dhu al Qa' da)and the month following (Muharram)were included in the prohibition, and Muharram was especially called al Haram. Possibly Muharram is meant in the first line, and the other months and other prohibited things in "all things prohibited". In Rajab also, war was prohibited. If the Pagan enemies of Islam broke that custom and made war in the prohibited months, the Muslims were free also to break that custom but only to the same extent as the others broke it. Similarly the territory of Makkah was sacred, in which war is prohibited. If the enemies of Islam broke that custom, the Muslims were free to do so to that extent. Any convention is useless if one party does not respect it. There must be a law of equality. Or perhaps the word reciprocity may express it better.

At the same time the Muslims are commanded to exercise self-restraint as much as possible. Force is a dangerous weapon. It may have to be used for self-defence or self-preservation, but we must always remember that self-restraint is pleasing in the eyes of ALLAH (Subhana Wa Ta' la). Even when we are fighting, it should be for a principle, not out of passion.