In one narration it is reported from Sayyiduna Ka'b (may Allah be pleased with him) that he said to the Prophet (peace and blessings be upon him): "Allah Almighty has revealed concerning poetry what He was to reveal." The Prophet (peace and blessings be upon him) said: "Indeed, the believer strives (performs jihad) with his life and his tongue." Then the narrator mentioned the hadith as before. Imam Ahmad recorded all these narrations with various chains, the narrators of one of which are the narrators of the Sahih. Al-Tabarani recorded something similar in al-Mu'jam al-Kabir and al-Mu'jam al-Awsat.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأدب / 13330