I. What is the sin and the voice of which the prophet speaks, and how may we ourselves be guilty of it? The father of modern philosophy and science has shown us that there are in the mind of man, as man, natural idols, which act as impediments to his acquisition of knowledge, and his search after truth. Till these idols are overthrown and broken in pieces and taken away, it is simply useless for man to pursue knowledge. His efforts will be neutralised, and their results vitiated. He will not arrive at truth. Now if this be true in the matter of human science it is not less worthy of our regard in the matter of Divine truth, and of the knowledge of God. We cannot know God, whom to know is eternal life, as long as these natural obstacles are not taken out of the way. What, then, is the practical bearing of this truth? (1) First there must be a single eye to the knowledge of God. If we have not made up our minds that the one only object worth living for is God, and the knowledge of God, we have set up idols in our hearts no less than the men in Ezekiel's time, who came and sat before him. (2) Not only must there be a clear perception of God as the one sole object of our services, but there must also be a readiness to sacrifice anything in order to know and to serve Him. The man who is not prepared at any cost to himself to know and to serve God, is not prepared to serve Him at all.
II. There are certain general principles to which it behoves us to give heed when we come to the worship of God. (1) First of all we must empty ourselves of ourselves. We must come as though our present knowledge of God were as nothing, and as if God were still to be known and learnt. (2) There is nothing which so infallibly prevents us from seeing the truth of God as secret sin. As long as sin, in one of its innumerable forms, lurks in the heart or on the conscience, the service of God will be a vain thing, because the pursuit of truth is a lie. It is that practised dishonesty, it is that cherished lust, it is that pampered self-love, it is that incurable indolence, which vitiates all your worship and renders your religion a lie.
S. Leathes, Church of England Pulpit,vol. viii., p. 209.