It must have pained Sarai to no end that she had given her slave girl to Abraham, and that her slave had given birth to a son. Sarai had thought she might have a son by the labors of her servant. She reasoned that if servants were for their master’s use, Hagar’s labor to bear a son would make that son hers, and by this, God’s promise would be realized. But this was not so. Sarai could not give Abraham a son of promise by the works of her slave girl. Neither the law, the works of man, nor the will of man can produce children to God. All who teach and preach and practice salvation by the will or work of man, whether in the beginning of it or in the middle or in the end, are slaves that can produce no fruit to God. God’s promises are not fulfilled by man's contribution, but by God's grace alone (Gal. 4:21-31). God’s work alone accomplish His promises.
The LORD instructed Moses to tell Pharaoh, “Let my people go that they may serve me” (Ex. 8:1). This command to Pharaoh foreshadowed the Gospel. Moses gave the law to Israel. The law requires personal obedience for life and blessings. It curses us for anything short of complete and perfect obedience. The law directs our attention to ourselves. It holds over us the threat of punishment. It holds out the hopeless promise of reward for obedience: hopeless, because we are sinners, and already under its curse, and because as sinners, we are disinclined and unable to do what it demands. But grace and truth came by Jesus Christ. The obedience required in the Gospel is faith in Christ. Faith directs all of our attention outside of ourselves to Christ. In believing, we see God has reconciled us to Himself by the death of His Son. This truth believed, is the spring of all worship. Believing Christ crucified, we know God. Believing Christ, we love God. Faith sees that Christ tore through the veil to reveal a reconciled God by His own blood. God dictated the conditions of peace. God was in Christ reconciling the world of His elect to Himself by the blood of His Son. To see God in Christ in His intention and work of reconciliation to us who made ourselves His enemies in our minds and by wicked works, and to see the cost He paid to fulfill His purpose, how can we not desire and love our God and Savior? Thus, “Let my people go that they may serve me” foreshadows Christ’s redeeming work. He destroyed the works of the devil. He redeemed us from all iniquity. He overcame the world. He subdued our iniquities. He cast our sins into the depths of the sea. We receive all of this grace through God’s gracious gift of faith. “Believe on the Lord Jesus Christ, and thou shalt be saved” (Acts 16:31). We want to serve our gracious God. None has ever been good to us but He. He is unchanging in His goodness (Rom. 11:29). He is eternal in His love (Jer. 31:3). He determined and accomplished our reconciliation in the death of His Son. You may wonder what you must do to make peace with God, to silence your screaming conscience. But God Himself has already made peace. He made peace in Christ (Col 1:20) when we were His enemies (Col. 1:21; Rom. 5:10). He tells this to us in the Gospel of Peace, through ministers He has sent. He even gives us faith, that persuasion of heart and conscience, that Christ is enough, that He is all in our salvation (Isa. 52:7; Rom. 10:15-17; 2 Cor. 5:18-21). This calls forth our heart’s admiration and worship. This is irresistible grace, given by the unfailing call of the Gospel to sinners (1 Tim 1:15)! All who hear this call (Acts 2:39; 1 Cor. 1:2; Heb. 9:15), see their deliverance from the Egyptian bondage of this world (Gal. 1:4), from satan (Luke 11:20-22; Col. 2:14-15; Heb. 2:14; 1 John 3:8; Rev. 12:9-11), of sin (Micah 7:18-20) and unbelief (Rom. 6:17). We are free and therefore now want to worship God in Christ and serve Him who released us from our sins and the curse of the law and captivity to satan!
Pastor Rick Warta