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Juwayriyyah, ummul mu'mineen, may Allah be pleased with her, narrated that once the Messenger of Allah PBUH went out of his apartment when she was offering the Morning Prayer. When he came back in the forenoon she was still sitting there. Observing this he said "I have recited 4 words 3 times after I left you and if these were to be weighted against what you have recited since morning then these would outweigh them: Subhan Allahi wa bihamdihi, 'aadada khalqihee wa ridha nafsihee wa zinaata arshihee wa midaada kalimaati (Glory be to Allah and praise is His (as great as) the number of His creatures, the extent of His satisfaction, the weight of His domain and the ink (needed to write down His countless) signs (of presence, omnipotence and grace)."Related by Muslim