A man said, “O Prophet of God, really the rules of Islām are many, tell me a thing by which I may lay hold of rewards.” The Prophet said, “Let your tongue be always moist in the remembrance of God.”
“Verily there are ninety-nine names of God; whosoever counts them up shall enter into Paradise.” And in another tradition it is added, “God is Witr and like Witr.”
When Ẕū ʾn-Nūn (Jonah) the prophet prayed his Lord, when he was in the fish’s belly, he said, “There is no Deity but Thee. I extol Thy holiness. Verily I am of the unjust ones.” And a Mussulman who supplicates God with this petition will have his prayer granted.
The best expressions are these four: Subhāna Allahi, al-Hamdu Lillāhi, La ilāha illā ʾllāhu, and Allāhu akbar; and it does not matter with which of them you begin.
Verily I like repeating these four expressions: O Holy God! Praise be to God! There is no deity but God! and God is Great! better than anything upon which the sun shines.
No one can bring a better deed on the Day of Resurrection (unless he shall have said the like or added to it) than he who has recited, “O Holy God! Praise be to Thee!” one hundred times every morning and evening.
There are two expressions light upon the tongue and heavy in the scale of good works, and they are, “O Holy God! Praise be to Thee!” and “O Holy God! the Mighty One!”
That person who shall say, “There is no deity but God, who has no partner, to whom is dominion and praise and power,” one hundred times, shall receive rewards equal to the emancipating of ten slaves; and one hundred good actions shall be written for him, and one hundred of his sins shall be blotted out; and those words shall be a protection to him from the devil and his wickedness, in that day in which he shall have repeated them, until the night. Nor can anyone perform a better deed for the Day of Resurrection than this, unless he has done even more.
Moses said, “O my Lord, teach me how I am to call upon Thee.” And God said, “O Moses, recite ‘There is no deity but God!’ ” Then Moses said, “O my Lord, every one of Thy people say this.” And God said, “O Moses, if the seven heavens and their inhabitants and the seven earths were put into one scale, and this expression, ‘There is no deity but God,’ into another, these words would exceed in weight.”
Reciting “O Holy God” is half the scale of good works, and reciting “God be praised,” fills the scale. The recital of “There is no deity but one,” removes the curtain between the worshipper and his God.