Isaiah 55:10-11

Isaiah 55:10-11. For as the rain cometh down, and the snow from heaven, and returneth not thither, but watereth the earth, and maketh it bring forth and bud, that it may give seed to the sower, and bread to the eater: So shall my word be that goeth forth out of my mouth: it shall not return unto me void, but is shall accomplish that which I please, and it shall prosper in the thing whereto I sent it.

Trust, then, in the gospel, which is the word of God, for it cannot fail you. Rest yourselves in the divine promise of pardon, for it cannot drop to the ground. It must accomplish the divine will.