All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, sallallaahu`alayhi wa sallam, is His slave and Messenger.
It has been proven that the Prophet, sallallaahu`alayhi wa sallam, said: “The miser is the one in whose presence I am mentioned and he does not send blessings upon me.” [Ahmed and At-Tirmidhi] They also reported the Hadeeth of Abu Hurayrah “May the man before whom I am mentioned – and he does not send blessings upon me – be humiliated.”
Some jurists, based on these Hadeeths, are of the view that it is obligatory to send blessings upon the Prophet, sallallaahu`alayhi wa sallam, every time his name is mentioned.
However, there is a difference of opinion among scholars. Some of them said it is obligatory to send blessings upon the Prophet, sallallaahu`alayhi wa sallam, every time his name is mentioned. Others said it is obligatory to send blessings upon him only once if his name was mentioned repeatedly in one sitting or gathering. However, the view of the Majority of Scholars is that sending blessings upon the Prophet whenever he is mentioned, is desirable and not obligatory and thus the one who does not do it is not sinning, even though he is called a miser.
There is also a difference in opinion regarding if the one who is praying reads or hears a verse in which the name of the Prophet is mentioned. Is it prescribed for him to send blessing upon him? Some said that it is recommended, but others said it is not recommended. For those who are of the view that it is recommended, it is sufficient for the one who is praying to say “” without mentioning his name, “Muhammad.” Some jurists even went to the point that he does not mention the name “Muhammad”, but rather he prays over him using the pronoun so that he does not repeat one of the pillars of the prayer, which is sending blessings upon the Prophet after the Tashahhud.
Allah knows best.