Musannaf Ibn Abi Shayba 28:1134

'Abd al-Rahim ibn Sulayman narrated to us, from Zakariyya, from Abu Ishaq, from Sa'id ibn Dhi Haddan, from Ali ibn Abi Talib, who said: "Indeed, Allah has decreed upon the tongue of His Prophet, may Allah bless him and grant him peace, that 'war is deception,' and I am a warrior who speaks about war." He said: "But when I say, 'The Messenger of Allah, may Allah bless him and grant him peace, said,' then by Allah, for me to fall from the sky is more beloved to me than to say about the Messenger of Allah, may Allah bless him and grant him peace, what he did not say."