COMPULSION:

2:256 - Let there be no compulsion in religion. Truth stands out clear from error; whoever rejects evil and believes in Allah hath grasped the most trustworthy hand-hold that never breaks. And Allah heareth and knoweth all things. 300 301

300 Compulsion is incompatible with religion; because 1) religion depends upon faith and will, and these would be meaningless if induced by force; 2) Truth and Error have been so clearly shown up by the mercy of God that there should be no doubt in the minds of any persons of goodwill as to the fundamentals of faith; 3) God's protection is continuous and His Plan is always to lead us from the depths of darkness into the clearest light. (2.256)

301 Hand-hold: something which the hands can grasp for safety in a moment of danger. It may be a loop or a handle, or anchor. If it is without flaw, so that there is no danger of breaking, our safety is absolutely assured so long as we hold fast to it. Our safety then depends on our own will and faith; God's help and protection will always be unfailing if we hold firmly to God and trust in Him. (2.256)

16:106 - Anyone who after accepting faith in Allah utters unbelief except under compulsion his heart remaining firm in faith but such as open their breast to unbelief on them is Wrath from Allah and theirs will be a dreadful Penalty. 2145

2145 The exception refers to a case like that of 'Ammar, whose father Yasir and mother Sumayya, were subjected to unspeakable tortures for their belief in Islam, but never recanted. 'Ammar, suffering under tortures himself and his mind acted on by the sufferings of his parents, uttered a word construed as recantation, though his heart never wavered and he came back at once to the Prophet, who consoled him for his pain and confirmed his faith. (16.106)

SEE:

Sahih Bukhari Hadith Subjects
Coercion

1. 'Except under compulsion and his heart...'
B 9.73

6. An example of hateful compulsion
B 9.81

Sahih Bukhari Hadith Subjects
Sadaqat Ul Fitr

8. Compulsion of Sadaqat-ul-Fitr
B 2.587