"So if I can't make any vocal sounds because I am a mute, are you going to prohibit me from making melody in my heart by playing a lute or other stringed instrument?"
Playing any type of instrument is not making melody in the heart.
Obviously you've never played a musical instrument... At least not well.
BTW if you are going to take that verse literally, as you seem to be doing, then if you are going to make melody in your heart, then you should simply attach a microphone to a stethescope and you guys can all listen to the melody from the heart. Obviously your vocal chords are not your heart and the vocal chords are an "instrument".
Sheesh.