Umar bin Khattab reported,
I heard the Messenger of Allah ﷺ say, "Allah 
forbids you from swearing by your fathers."Umar said, "By Allah, I have not sworn by them since I heard the Messenger of Allah ﷺ forbid it, nor have I uttered such an oath, neither on my own behalf nor reporting it from someone else."
Ahmad 112
Sahihحدثنا بشر بن شعيب بن أبي حمزة قال حدثني أبي عن الزهري قال أخبرني سالم بن عبد الله أن عبد الله بن عمر أخبره أن
عمر بن الخطاب رضي الله عنه قال
سمعت رسول الله ﷺ يقول إن الله عز وجل ينهاكم أن تحلفوا بآبائكم قال عمر فوالله ما حلفت بها منذ سمعت رسول الله ﷺ نهى عنها ولا تكلمت بها ذاكرا ولا آثرا
Its chain of transmission is sahih. Bishr bin Shuayb is trustworthy. Some critics found fault with his hearing from his father, but here, and repeatedly in what follows, such as in 11860, 13385, and 13386, he explicitly states that he heard directly from him. Some have claimed that Ahmad refrained from narrating from him, even though his hadith is established in the Musnad, as you can see."Neither remembering nor reporting" means, I did not speak it on my own initiative, nor did I relate on the authority of anyone that he swore by it, athar being what is reported from someone else.