Who said: "Were it not for Ali, Umar would have perished"? Thank you.

This statement has been reported in some books and attributed to Umar ibn al-Khattab, may Allah be pleased with him. Among those who mentioned it is al-Hafiz Ibn Abd al-Barr in his book "Al-Isti'ab," where Umar said: "Were it not for Ali, Umar would have perished," after Ali explained to him the ruling concerning an insane woman who gave birth after six months, citing Allah's saying: (And his gestation and weaning [period] are thirty months), and that the pen is lifted from the insane.