George Leo Haydock

If we believe not; i.e. if we refuse to believe in God, or if after having believed, we depart from our faith, the Almighty still continues faithful; he is still what he was. Our believing in him cannot increase his glory, nor can our disbelief in him cause any diminution thereof, since it is already infinite. (Estius) — The sense may be: when we renounce God, and refuse to believe in him, will he be less powerful to punish us? or, will his menaces be less true or less efficacious? He will effect his work without us, for he will infallibly bring about the salvation of his elect. (Bible de Vence)