We can now in some measure estimate the value of the Apostle’s description of faith as an assurance concerning things hoped for, and apply it to give force to the exhortations of the Epistle. The evil heart of unbelief is the moral corruption of the man whose soul is steeped in sensual imaginations and never realises the things of the Spirit. They who came out of Egypt by Moses could not enter into rest because they did not descry, beyond the earthly Canaan, the rest of the spirit in God. Others inherit the promises, because on earth they lifted their hearts to the heavenly country. In short, the Apostle now tells his readers that the true source of Christian constancy and boldness is the realisation of the unseen world. But faith is this assurance concerning things hoped for because it is a proof[255] of their existence, and of the existence of the unseen generally. The latter part of the verse is the broad foundation on which faith rests in all the rich variety of its meanings and practical applications. Here St. Paul, St. James, and the writer of the Epistle to the Hebrews meet in the unity of their conception. Whether men trust unto salvation, or develop their inner spiritual life, or enter into communion with God and lift the weapon of unflinching boldness in the Christian warfare, trust, character, confidence, all three derive their being and vitality from faith, as it demonstrates the existence of the unseen. The Apostle’s language is a seeming contradiction. Proof is usually supposed to dispense with faith and compel us to accept the inference drawn. He intentionally describes faith as occupying in reference to spiritual realities the place of demonstration. Faith in the unseen is itself a proof that the unseen world exists. It is so in two ways. _First_, we trust our own moral instincts. Malebranche observes that our passions justify themselves. How much more is this true of intellect and conscience! In like manner, some men have firm confidence in a world of spiritual realities, which eye has not seen. This confidence is itself a proof to them. How do I know that I know? It is a philosopher’s enigma. For us it may be sufficient to say that to know and to know that we know are one and the same act. How do we justify our faith in the unseen? The answer is similar. It is the same thing to trust and to trust our trust. Scepticism wins a cheap victory when it arraigns faith as a culprit caught in the very act of stealing the forbidden fruit of paradise. But when, like a guilty thing, faith blushes for its want of logic, its only refuge is to look in the face of the unseen Father. He who has most faith in his own spiritual instincts will have the strongest faith in God. To trust God is to trust ourselves. To doubt ourselves is to doubt God. We must add that there is a sense in which trust in God means distrust of self.