The Prophet ﷺ heard Umar saying, "By my father." The Messenger of Allah ﷺ said, "Allah forbids you to swear by your fathers. Whoever among you wishes to swear an oath, let him swear by Allah or remain silent."Umar said, "I never swore by it again after that, neither on my own nor quoting another."
حدثنا عبد الأعلى عن معمر عن الزهري
أن النبي ﷺ سمع عمر وهو يقول وأبي فقال رسول الله ﷺ إن الله ينهاكم أن تحلفوا بآبائكم فإذا حلف أحدكم فليحلف بالله أو ليصمت قال عمر فما حلفت بها بعد ذاكرا ولا آثرا
Its isnad is sahih, and Bukhari and Muslim and others narrated it, as in Muntaqa 4862. Something similar in meaning has already passed from the narration of Abdullah bin Umar from his father Umar, 112, 241, and something similar has also passed from the narration of Ibn Abbas from Umar, 214, 240, see also 329. Something similar will also come, 4548, 4593.