Is it permissible to send blessings upon the Prophet (peace and blessings be upon him) during prostration in prayer, and thereby say, “O Allah, send blessings upon our master Muhammad”?

Question:
Does sending blessings upon the Prophet (peace and blessings be upon him) during prostration in prayer increase?

Answer:
And thereby we say, “O Allah, send blessings upon our master Muhammad.” The place for sending blessings upon the Prophet (peace and blessings be upon him) is in the tashahhud, not in the prostration. In prostration, one does not say, “Glory to my Lord, the Most High.” Rather, one makes du'a' (supplication) in prostration and increases in du'a'.
His saying (peace and blessings be upon him), “As for prostration, increase in du'a'.” He said, “The most likely to be answered is your prostration.” It is not permissible to liken Allah (Glorified and Exalted is He) when He says, “Glory to our Lord, the Most High.” This is obligatory in prostration once, and what is added to it is a sunnah (recommended practice). Also, one supplicates to Allah (Mighty and Majestic) with whatever supplications are easy for him. As for sending blessings upon the Prophet (peace and blessings be upon him), its place is in the tashahhud.