It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Supplicate to Allah while you are fully certain of its acceptance, and know that Allah Almighty does not accept the supplication of a heedless heart occupied with amusement." The chain of this hadith is sound; only Salih al-Murri narrated it, and he is one of the ascetics of Basrah, and the two Shaykhs did not record it.