Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: My father, Sayyiduna Abbas (may Allah be pleased with him), said to me: My son, the Commander of the Believers calls you, brings you close and consults you along with the Companions of the Messenger of Allah (peace and blessings be upon him), so remember three things from me: Beware! Let him never catch you in a lie; never disclose a secret of his; and never backbite anyone in his presence. Amir (al-Sha'bi) said: I said to Sayyiduna Ibn Abbas (may Allah be pleased with them both): Each one of these is better than ten thousand.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10573