Al-Matalib al-'Aliyah 3677 — Surah al-Shu'ara

It is narrated from Ubaydullah bin Ka'b bin Malik that when this noble verse was revealed: "And the poets, it is the deviators who follow them" [Surah al-Shu'ara: 224], the Messenger of Allah (peace and blessings be upon him) said (making clear the importance of believing poets): "Indeed, the believer strives (for the religion) with both his hand and his tongue. By the One in whose hand is my soul! (These verses of yours against the disbelievers) are as cutting as if you were attacking them with arrows."
Abu Ya'la narrated this hadith in his Musnad. In its chain, the narrator Salih bin Abi al-Akhdar has been criticised on account of his memory; however, there are corroborating reports for it in sahih narrations.