Reference: Fataawa al-‘Aqeedah – Page 589, Question 630
Question: At the beginning of the prayer, some people verbally pronounce: “I have made the intention to pray such-and-such as an obligation upon me for the Sake of Allaah the Exalted…”. So what is the ruling regarding this declaration, and may Allaah bless you?
Response: That which the questioner has asked, in that some of the worshipers verbally pronounce the intention before the prayer by saying “I have made the intention to pray such-and-such” – then this is from the innovations which Allaah has not legislated, and nor has it been established from the Prophet (sal-Allaahu ‘alayhi wa sallam), and nor from his companions and the rightly guided successors, and nor from any of the first three generations, and nor from any of the recognised imaams that they ever said this at the beginning of the prayer or other than it from the other acts of worship. Rather, they would make the intention in their hearts, since the place of the intention is in the heart and not upon the tongue. Allaah (‘Azza wa Jall) says:
So this is from the innovations, and it is not permissible to continue to do this; Rather, the Muslim is required to make the intention in his heart, and intend in his heart to perform an act of worship which Allaah has legislated, without verbally pronouncing it – this is because verbally pronouncing the intention is from the newly innovated matters.
As for what has been attributed to ash-Shaafi’ee (rahima-hullaah) that he was of this opinion, then this has not been established from him, rather, that which is established from him is that he said: “Indeed (regarding) the prayer, then it is imperative to be vocal at its beginning”. And what he intended by this (statement) is the vocal pronouncing of the takbeeratul-ihraam [the saying of Allaahu Akbar at the beginning of the prayer], and the meaning of his words was not that the intention of the prayer must be verbally pronounced.