Mu'jam Kabir Tabarani 17509 — Sayyiduna Mu'adh bin Jabal said: I said

Abu Salamah (may Allah have mercy on him) said that Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) said: I said: "O Messenger of Allah, advise me." He (peace and blessings be upon him) said: "Worship Allah as though you see Him, count yourself among the dead, remember Allah, the Mighty and Majestic, beside every stone and every tree, and when you commit an evil deed, do a good deed right alongside it: the hidden (sin expiated) by a hidden (good deed), and the open (sin expiated) by an open (good deed)." Then he said: "Shall I not tell you of what gives people more control than all of that?" I said: "Certainly, O Messenger of Allah." So he (peace and blessings be upon him) took hold of the tip of his tongue. I said: "O Messenger of Allah!" - as though he considered it a trivial matter - and the Prophet (peace and blessings be upon him) said: "Is it not this (tongue) alone that throws people on their noses into Hell?" And he (peace and blessings be upon him) again took hold of the tip of his tongue.