They were concealing in their hearts that they show not to thee , saying , ' Ah , if we had had a part in the affair , never would we have been slain here . ' Say : ' Even if you had been in your houses , those for whom slaying was appointed would have sallied forth unto their last couches ' ; and that God might try what was in your breasts , and that He might prove what was in your hearts ; and God knows the thoughts in the breasts .