Hadith 951:4
'Abd al-Razzaq narrated to us, Ma'mar informed us, from al-Zuhri, from Ibn al-Musayyib, who said: Hassan ibn Thabit recited poetry while he was in the mosque. 'Umar passed by him and glanced at him. Hassan said: "By Allah, I have recited poetry in it [the mosque] before someone who is better than you." He feared that he [Hassan] might strike him with [the mention of] the Messenger of Allah, may Allah bless him and grant him peace, so he passed by and left him.
حدثنا عبد الرزاق، أخبرنا معمر، عن الزهري، عن ابن المسيب، قال: أنشد حسان بن ثابت وهو في المسجد، فمر به عمر فلحظه، فقال حسان: " والله لقد أنشدت فيه من هو خير منك ". فخشي أن يرميه برسول الله صلى الله عليه وسلم فجاز وتركه