It is narrated from Sayyiduna Abdullah bin Busr (may Allah be pleased with him) that a Bedouin said to the Messenger of Allah (peace and blessings be upon him): (O Messenger of Allah (peace and blessings be upon him),) the injunctions of Islam (voluntary acts of worship and obligations) have become too many for me, so tell me of some (comprehensive) thing that I may hold on to firmly. He (peace and blessings be upon him) said: "Let your tongue always remain moist with the remembrance of Allah." This hadith is sahih al-isnad (its chain is authentic), but the two Shaykhs (Bukhari and Muslim) did not record it.