Now, it must be admitted that if we ourselves had aught to do with the ground of certainty or assurance, then it would indeed be the very height of folly to think of being sure; then assuredly our hope would be a very vague one. But, thanks be to God, it is not so. We having nothing whatever to do with the ground of our certainty, it lies entirely outside of ourselves, and it must be sought only and altogether in the eternal word of God. This renders it blessedly simple. It makes the whole question hinge upon the truth of God's word. Why am I sure? Because God's word is true. A shadow of uncertainty or misgiving on my part would argue a want of authority or security in the word of God. It really comes to this: Christian certainty rests on the faithfulness of God. Before you can shake the former, you must shake the latter. We can understand this simple principle by our dealings with one another. If my fellow man makes a statement to me, and I express the smallest doubt or misgiving, or if I feel it without even expressing it, I am calling in question his truthfulness, or credibility. If he is a faithful, competent authority, I have no business to entertain a single doubt. My certainty is linked with his credibility. If he is a competent authority, I may enjoy perfect repose as to the matter concerning which he has spoken. Now, we all know what it is to receive in the most unqualified way the testimony of man, and to repose with calmness therein. It is not a question of feeling, but of receiving without a single question a plain statement, and resting on the authority of a competent witness. Well, then, as we have it in the First Epistle of John, "If we receive the testimony of man, the testimony of God is greater." So, also, our Lord said to the men of His time, "If I say the truth, why do ye not believe Me?" (John viii.) He appeals to the truth of what He says as the reason why, or the ground on which, He expected to be believed.