Why wasn't the Virgin Mary's sin passed on to Jesus?

The sinlessness and perfection of Jesus Christ are important because unless Jesus was sinless, he couldn't be the Redeemer of God's elect (WSC, Q/A 21). He was and still is sinless (2 Cor. 5:21; Heb. 4:15; 1 Pet. 2:22; 1 John 3:5; cf. 1 Pet. 1:18-19). The writer of Hebrews says this of Jesus: "[It] was indeed fitting that we should have such a high priest, holy, innocent, unstained, separated from sinners, and exalted above the heavens" (Heb. 7:26).

The eternal Son of God took to himself flesh (John 1:14). The Westminster Shorter Catechism Q/A 22 summarizes this truth saying:

Christ, the Son of God, became man, by taking to himself a true body and a reasonable soul, being conceived by the power of the Holy Ghost, in the womb of the Virgin Mary, and born of her, yet without sin.

Jesus is the sinless God-man. Christ existed before he came as a man (John 3:13; 6:33, 38, 62; 8:23; 16:28; Rom 8:3; Gal 4:4; 1 John 1:2). Jesus himself taught his own pre-existence when he said, "And now, Father, glorify me in your own presence with the glory that I had with you before the world existed" (John 17:5: cf. John 8:59-59). Jesus Christ is also the Creator of the universe (John 1:2-3; Col 1:16-17; Heb 1:2). So, without a doubt Jesus Christ existed in eternity and is the eternally sinless very God of very God (Psa 11:7; Hab 1:13; Tit 1:2).

Theologically, the phrase “hypostatic union” correctly maintains that Christ is fully God and fully man in one indivisible person — the God-man, Jesus Christ. Biblically, Jesus Christ needed to be fully divine in order to offer a pure and holy sacrifice to satisfy God the Father, just as he also needed to be fully a sinless man (2 Cor 5:21; Heb 7:26) to die for men (Rom. 5:12-19). As such Jesus is the second and last man Adam (1 Cor. 15:45, 47).

However, Mary, his mother, was a sinner (Rom. 3:23; 6:23). She admitted this when she said, "My soul magnifies the Lord and my spirit rejoices in God my Savior” (Luke 1:46-47). So, how could this sinless person, Jesus, come from the sinful Mary who acknowledged the need of a Savior?

Matthew wrote that Mary was found to be with child from the Holy Spirit (Matt. 1:18). An angel told Joseph “that which is conceived in her [Mary] is from the Holy Spirit" (Matt. 1:20), and thus Jesus had no sinful human birth father. Jesus’ conception was a supernatural union of the divine and a human nature through the agency of the Holy Spirit. Mary herself left human agency out of the equation of the incarnation when she asked, "How will this be, since I am a virgin?" (Luke 1:34). This was answered by an angel of the Lord who said, "The Holy Spirit will come upon you, and the power of the Most High will overshadow you; therefore the child to be born will be called holy — the Son of God" (Luke 1:35). So, Mary became the bearer of the Holy One of God - the God-Man, the sinless Jesus Christ.

This is how we can say that Christ, who knew no sin, became sin to die in the place of his people (2 Cor. 5:21; cf. Rom. 5:6, 8, 10) He is the Savior of God's elect.

Related Topics

What is the Immaculate Conception?
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