And that He might know the hypocrites; and it was said to them: Come, fight in Allah's way, or defend yourselves. They said: If we knew fighting, we would certainly have followed you. They were on that day much nearer to unbelief than to belief. They say with their mouths what is not in their hearts, and Allah best knows what they conceal.

It shall be no crime in the weak, nor in the sick, nor in those who do not find what they should spend (to stay behind), so long as they are sincere to Allah and His Messenger; there is no way (to blame) against the doers of good; and Allah is Forgiving, Merciful;