Is the supplication format: "O Allah, I bear witness before You, and before the bearers of Your Throne, Your angels, and all of Your creation, that You are Allah, there is no god but You, the One, the Self-Sufficient, Who begets not nor is begotten, and there is none comparable to Him; and I bear witness that Muhammad is Your servant and Your Messenger" sound, and is it permissible to supplicate with it at any time?

It is recommended to supplicate with the reported supplications authentically established from the Prophet, peace and blessings be upon him. The Sunnah contains hadiths that indicate supplications encompassing "the Greatest Name," among which are the supplication, "O Allah, I ask You, by my testimony that You are Allah, there is no god but You, the One, the Self-Sufficient, who neither begets nor is begotten, and there is none comparable to Him," and the supplication, "O Allah, I ask You, for all praise is due to You, there is no god but You, the Bestower, the Originator of the heavens and the earth, O Possessor of majesty and honor, O Ever-Living, O Self-Sustaining, I ask You." Supplicating with these formulas is better, even though it is permissible to supplicate with other lawful supplications.