4. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from ibn Mahbub from Muhammad ibn Qaza‘ah who has said the following: “I once said to abu ‘Abd Allah , ‘We are told that Ibrahim ‘Alayhi al-Salam circumcised with an adze on a base. He (the Imam) said, ‘Allah is free of all defects, it is not the way they say it is. They have lied against Ibrahim.’ I then asked, ‘How did it happen?’ He (the Imam) said, ‘In the case of the prophets, ‘Alayhim al-Salam, it would drop off on its own as well as their umbilical cord on the seventh day. When a child was born to Ibrahim , from Hagar, Sarah reproached her as slave-girls are reproached and she wept. It caused her an intense feeling and when Ismail saw her weep he also wept because of her weeping. Ibrahim came in and asked Ismail, ‘What has made you weep?’ Ismail replied, “Sarah reproached my mother with such and such words. She wept and I also wept.” Ibrahim then stood on his place for prayer, spoke to his Lord and asked to make it drop from Hagar. Allah caused it to drop off. When Sarah gave birth to Ishaq and it became the seventh day the umbilical cord of Ishaq fell off but not the cover to be circumcised. Sarah became frightened thereby. When Ibrahim came in she said, ‘O Ibrahim, what is this incident which has taken place with the family of Ibrahim and the children of prophets? This is your son Ishaq. His umbilical cord has fallen off but not his circumcision place.’ Ibrahim stood in the place of his prayer, spoke to his Lord and asked, ‘O Lord, what is this incident that has taken place in the family of Ibrahim and the children of prophets? This is my son Ishaq. His umbilical cord has fallen off but not his circumcision place. Allah, most High, sent him revelation that said, ‘O Ibrahim this is because when Sarah reproached Hagar I then swore not to allow the circumcision place of one of the children of the prophets to fall off because of Sarah’s reproaching Hagar. Thus circumcise Ishaq with iron and make him to feel the heat of iron.’ He (the Imam) said, ‘Ibrahim circumcised him with iron; then the tradition continued in the children of Ishaq thereafter.’”