All languages, I suppose.
The real issue is that our description of God will always be as accurate as an ant's understanding of a human being.
As humans, we may say that God "speaks" to us, or we may speak of God's "hands"....we even call God "He".... and this is the best we can do. Unfortunately, the use of a language that consists solely of sounds and words and symbols really limits us. We do not understand or know God's full language, and therefore do not have the words (or the language!) to describe it.
God's language may be revealed through nature or a kind gesture, for example. For one who believes in an infinite God, it is impossible to put into words something so immense.