[2:217] They ask you about the sacred month, and fighting in it. Say, 'Fighting in it is a grave thing; but to bar from God's way, and disbelief in Him, and the Sacred Mosque, and to expel its people from it - that is graver in God's sight; and sedition
is graver than slaying'.
Among disobedient acts, there is that which is more intense than others and more difficult to conceptualize. Bad manners at the door do not bring about what they would bring about on the carpet. When the error occurs through the lower self, it affects it through the deferred punishment, which is burning (iḥtirāq). When the heart errs, the punishment is immediate, and it is through separation (firāq). The effect of heedlessness on hearts is more serious than the harm caused by error to the lower selves, for surely the lower self is kept from good fortune, but the heart is kept from the Real.
[2:217 cont'd] They will not cease to fight against you until they turn you from your religion if they are able; and whoever of you turns from his religion, and dies disbelieving - their works have failed in this world and the Hereafter. Those are the inhabitants of the Fire, abiding therein.
The allusion in this is to the people of heedlessness when they seek to lure you away, wanting to turn you towards their heedlessness. They will only be content when you break the contract of your spiritual desire (irāda) by returning to your previous state. Anyone who breaks (fasakha) his contract with God deforms (masakha) his heart.