Sacred Months
Fighting in the sacred months is serious, but retaliation is allowed. If they attack you, then respond in kind. However, be mindful of Allah and know that He is with those who are conscious of Him.
2:194The forbidden month for the forbidden month, and forbidden things in retaliation. And one who attacketh you, attack him in like manner as he attacked you. Observe your duty to Allah, and know that Allah is with those who ward off (evil).
They ask you about fighting in the sacred month. Say, ‘Fighting in it is a grave matter, but hindering people from Allah’s path, denying Him, preventing access to the Sacred Mosque, and expelling its people from it, these are far worse in Allah’s sight.
2:217They question thee (O Muhammad) with regard to warfare in the sacred month. Say: Warfare therein is a great (transgression), but to turn (men) from the way of Allah, and to disbelieve in Him and in the Inviolable Place of Worship, and to expel His people thence, is a greater with Allah; for persecution is worse than killing. And they will not cease from fighting against you till they have made you renegades from your religion, if they can. And whoso becometh a renegade and dieth in his disbelief: such are they whose works have fallen both in the world and the Hereafter. Such are rightful owners of the Fire: they will abide therein.
When the sacred months have passed, then fight the polytheists wherever you find them, capture them, besiege them, and lie in wait for them at every ambush. But if they repent, establish prayer, and give charity, then let them go their way.
9:5Then, when the sacred months have passed, slay the idolaters wherever ye find them, and take them (captive), and besiege them, and prepare for them each ambush. But if they repent and establish worship and pay the poor-due, then leave their way free. Lo! Allah is Forgiving, Merciful.
The number of months with Allah is twelve, as decreed on the day He created the heavens and the earth. Four of them are sacred. This is the correct religion, so do not wrong yourselves in them. Fight the polytheists collectively, as they fight you collectively.
9:36Lo! the number of the months with Allah is twelve months by Allah's ordinance in the day that He created the heavens and the earth. Four of them are sacred: that is the right religion. So wrong not yourselves in them. And wage war on all of the idolaters as they are waging war on all of you. And know that Allah is with those who keep their duty (unto Him).