The ruling on the intention of a mute person for the takbir in prayer

The questioner : If its obligation is established, but a person is unable to perform it because he is mute and does not know how or cannot speak, is it dropped from him? Or does he intend it with his heart, or move his tongue and lips?

The Shaykh : We say, rather, he intends it with his heart. Indeed, he intends it with his heart, because a person’s saying “Allahu Akbar” encompasses the speech of the tongue and the speech of the heart. Is that not so? He did not say “Allahu Akbar” with his tongue except when he said it with his heart and resolved to do so. So, if speaking with the tongue becomes impossible, what then?
The speech of the heart becomes obligatory, so he says it with his heart and does not move his tongue and lips. This is contrary to the view of some scholars who said that he should move his tongue and lips, because speech involves moving the tongue and lips. So, when the voice becomes impossible, the movement becomes obligatory. Do you understand? Well, we say in response to this: Is the movement of the tongue and lips intended for its own sake or for something else? It is intended for something else, because speech is not achieved except through it. So, when the primary intended object becomes impossible, the means is dropped.
And this means becomes mere movement and futility. What is the benefit of a person moving his lips and tongue when he cannot speak and cannot obey? The stronger position in this issue is that if a person is mute and cannot say it with his tongue, he intends it with his heart and does not move his lips or tongue, because that is futility and movement in prayer that is not needed.