1. _The presence of God is the great privilege of God's people, and their only power against the enemy._--God had promised to Moses, _I will bring you in_ unto the land. Moses proved that he understood this when God, after the sin of the golden calf, spoke of withdrawing His presence and sending an angel. He refused to accept anything less than God's presence. "For whereby shall it be known that I and Thy people have found grace in Thy sight? Is it not that _Thou goest with us_?" It was this gave Caleb and Joshua their confidence: The Lord is with us. It was this gave Israel their victory over Jericho: the presence of God. This is throughout Scripture the great central promise: I am with thee. This marks off the whole-hearted believer from the worldling and worldly Christians around him: he lives consciously hidden in the secret of God's presence. 2. _Defeat and failure are always owing to the loss of God's presence._--It was thus at Ai. God had brought His people into Canaan with the promise to give them the land. When the defeat at Ai took place Joshua felt at once that the cause must be in the withdrawal of God's power. He had not fought for them. His presence had been withheld. In the Christian life and the work of the Church, defeat is ever a sign of the loss of God's presence. If we apply this to our failure in the prayer-life, and as a result of that to our failure in work for God, we are led to see that all is simply owing to our not standing in clear and full fellowship with God. His nearness, His immediate presence, has not been the chief thing sought after and trusted in. He could not work in us as He would. Loss of blessing and power is ever caused by the loss of God's presence. 3. _The loss of God's presence is always owing to some hidden sin._--Just as pain is ordered in nature to warn of some hidden evil in the system, defeat is God's voice telling us there is something wrong. He has given Himself so wholly to His people, He delights so in being with them, and would so fain reveal in them His love and power, that He never withdraws Himself unless they compel Him by sin. Throughout the Church there is a complaint of defeat. The Church has so little power over the masses, or the educated classes. Powerful conversions are comparatively rare. The fewness of holy, consecrated, spiritual Christians, devoted to the service of God and their fellowmen, is felt everywhere. The power of the Church for the preaching of the gospel to the heathen is paralysed by the scarcity of money and men; and all owing to the lack of the effectual prayer which brings the Holy Spirit in power, first on ministers and believers, then on missionaries and the heathen. Can we deny it that the lack of prayer is the sin on account of which God's presence and power are not more manifestly seen among us?