Where lies the secret strength of faith? It lies in the food it feeds on; for faith studies what the promise is–an emanation of divine grace, an overflowing of the great heart of God; and faith says, “My God could not have given this promise, except from love and grace; therefore it is quite certain his Word will be fulfilled.” Then faith thinketh, “Who gave this promise?” It considereth not so much its greatness, as, “Who is the author of it?” She remembers that it is God who cannot lie–God omnipotent, God immutable; and therefore concludeth that the promise must be fulfilled; and forward she advances in this firm conviction. She remembereth,why the promise was given,–namely, for God’s glory, and she feels perfectly sure that God’s glory is safe, that he will never stain his own escutcheon, nor mar the lustre of his own crown; and therefore the promise must and will stand. Then faith also considereth the amazing work of Christ as being a clear proof of the Father’s intention to fulfil his word. “He that spared not his own Son, but freely delivered him up for us all, how shall he not with him also freely give us all things?” Moreover faith looks back upon the past, for her battles have strengthened her, and her victories have given her courage. She remembers that God never has failed her; nay, that he never did once fail any of his children. She recollecteth times of great peril, when deliverance came; hours of awful need, when as her day her strength was found, and she cries, “No, I never will be led to think that he can change and leave his servant now. Hitherto the Lord hath helped me, and he will help me still.” Thus faith views each promise in its connection with the promise-giver, and, because she does so, can with assurance say, “Surely goodness and mercy shall follow me all the days of my life!”
Charles Spurgeon