If he is mentally ill then maybe he can't comprehend or grasp the word of God. But I know God uses people, experiences, and other works in earth to get us to get closer to him. I will pray that God sends the right people, right resources, right doctors, the right therapy and everything in his power that can lead this young man to walk with God. I pray God help heals his traumas and give him the strenght to to be born again. Amen