It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Indeed, Allah Almighty has distributed your characters among you just as He has distributed your provisions among you. Allah Almighty gives wealth to those He loves and to those He does not love, but He gives faith only to those He loves. So whoever Allah has given faith, He has loved him. By the One in whose Hand is the soul of Muhammad ((peace and blessings be upon him))! No servant is (truly) a Muslim until his heart submits (to Allah), and no servant is a believer until his neighbour is safe from his bawa'iq (evils and harms)." This hadith has a sahih (authentic) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.