And Joshua said unto the people, Ye cannot serve the Lord. Joshua 24:19 In answer to Joshua's challenge, the people had said, "We will serve the Lord, for he is our God." But Joshua knew them too well to trust them, and reminded them that they were undertaking, what they could not perform. They did not believe him, but cried, "Nay, but we will serve the Lord"; but their after history proved the truth of Joshua's warning. God's word knows us better than we know ourselves. God's omniscience sees each part of our being as an anatomist sees the various portions of the body, and he therefore knows our moral and spiritual nature most thoroughly. A watchmaker is the best judge of a watch; and he who made man has the best knowledge of his condition and capacity. Let us dwell upon his verdict as to human ability.

I. THE CERTAINTY OF THE TRUTH THAT UNRENEWED MEN CANNOT SERVE GOD.

It is not a physical but a moral inability, and this is not in their nature, but in their fallen nature; not of God, but of sin. It may be said that they could serve God if they liked; but in that "if" lies the hinge of the whole question. Man's inability lies in the want of moral power so to wish and will as actually to perform. This leaves him with undiminished responsibility; for he ought to be able to serve God, and his inability is his fault (Jer. 13:23).

1. The nature of God renders perfect service impossible to depraved men. "Ye cannot serve the Lord, for he is a holy God, he is a jealous God." See context

2. The best they could render as unrenewed men would lack heart and intent, and therefore must be unacceptable. Without love and faith men cannot please God. What are the prayers, alms, and worshippings of a Christless soul (Isa. 1:15)?

3. The law of God is perfect, comprehensive, spiritual, far-reaching: who can hope to fulfill it? If a look may commit adultery, who shall in all points keep the law (Matt. 5:28)?

4. The carnal mind is inclined to self-will, self-seeking, lust, enmity, pride, and all other evils. "It is not subject to the law of God, neither indeed can be" (Rom. 8:7).

5. Let men try to be perfectly obedient. They will not try it. They argue for their ability, but they are loth enough to exert it.

II. THE DISCOURAGEMENT WHICH ARISES FROM THIS TRUTH.

It is alleged that this will drive men to despair, and our reply is that the kind of despair to which it drives men is most desirable and salutary.

1. It discourages men from an impossible task. They might as well hope to invent perpetual motion as to present a perfect obedience of their own, having already sinned. If a man should try to hold up a ladder with his own hand, and at the same time climb to the top of it, he would have less difficulty than in causing his evil nature to attain to holiness.

2. It discourages from a ruinous course. Self-righteousness is a deadly thing; it is a proud refusal of mercy, and a rebellion against grace. Self-confidence of any sort is the enemy of the Savior.

3. It discourages reliance upon ceremonies or any other outward religiousness, by assuring men that these cannot suffice.

4. It discourages from every other way of self-salvation, and thus shuts men up to faith in the Lord Jesus. Nothing better can befall them (Gal. 2:22-23). III. THE NECESSITIES OF WHICH WE ARE REMINDED BY THIS TRUTH. Unregenerate men, before you can serve God you need: · A new nature, which only the Spirit of God can create in you: the old man cannot serve the Lord. An impure fountain must pour out foul streams. The tree must be made good, or the fruit will not be good. · Reconciliation. How shall an enemy serve his king? There must be forgiveness, friendship, mutual delight. God and you must be made friends through the Mediator, or else you cannot be the servant of God. · Acceptance. Till you are accepted, your service cannot please God. Only a perfect righteousness can make you accepted of a holy and jealous God; and none but Jesus can give you a complete justification. · Continued aid. This you must have to keep you in the way when once you are in it (1 Sam. 2:9; Jude 24:25). · If you cannot serve God as you are, yet trust him as he manifests himself in Christ Jesus; and do this just as you are. · This will enable you to serve him on better principles. · This change of your nature will be effected by the Holy Spirit, who will come and dwell in you. · This will fit you for heaven, where "his servants shall serve him."