Ibn ‘Umar said

The Prophet (ﷺ) sent Khalid b. al-Walid to the B. Hadhima and he summoned them to accept Islam. When they did not express their acceptance of Islam properly but began to say, “We have changed our religion, we have changed our religion,”* Khalid began to kill them and take prisoners, and he handed a prisoner to each one of us. But when a day came when Khalid ordered each of us to kill his prisoner, I said, “I swear by Allah that I will not kill my prisoner and that not one of my companions will kill his prisoner till we come to the Prophet.” When we mentioned the matter to him he raised his hands and said twice, “O Allah, I declare myself innocent in Thy sight of what Khalid has done.” *Here the verb saba'a is used. Bukhari transmitted it.