Jesus was necessary because mankind, as a result of Adam’s sin/disobedience, fell under the curse of sin as children of Adam. Our sin created a chasm, a divide, between mankind and God because our God is perfect holiness, righteousness, justice, and God will not permit sin to dwell in His Kingdom and God will not permit sin to go unpunished and without judgment (Revelation 21:27; Ecclesiastes 12:14); therefore, without a Mediator for our sin, mankind has no hope of life in Eternity but only death in sin and death in Hell (Acts 4:12).
As a result of our sin, we enter the World spiritually dead (Ephesians 2:1; Colossians 2:13) and our bodies also die physiologically/physically because of sin (Romans 6:23; 1 Corinthians 15:22). God the Father, to indicate how serious sin actually is, mandated that ONLY sinless, perfect, blood would be acceptable as payment for sin (Leviticus 17:11); unfortunately, the blood of animals could NOT take away sin (Hebrews 10:4-6); therefore, God Himself left eternity and entered Time through the womb of a virgin (Philippians 2:8; Matthew 1:23). It was necessary that Jesus be born of a virgin in order to avoid the seed of Adam through Joseph, because it is the seed of Adam, the man, that transmits the sin-nature to all of mankind (1 Corinthians 15:22).
Jesus is the ONLY One who is both “sinless” and therefore “acceptable” to God the Father as a sacrifice for sin; for this reason, God gave His only Son to die in our place so that we could receive Jesus’ perfection, His righteousness over our life and by doing so, we can find forgiveness of sin and life in Eternity with God the Father (2 Corinthians 5:21). Without Jesus as our Lord and Mediator for sin, mankind has no hope of life in God’s Kingdom (John 8:24).
How can one receive forgiveness of sin and life in Eternity with God the Father?
It is by repenting of our sin (turning away from wilful sin) (Acts 17:30), believing in our heart, confessing with our mouth that Jesus is God who died to pay our sin-debt and that He was resurrected for our justification…it is by believing and confessing Jesus as our Lord that we find righteousness (a right standing) with God the Father through the forgiveness of sin (Romans 10:9-10; Romans 10:13; Acts 2:21). There is no other way to find forgiveness of sin and life with God the Father but through faith in Jesus Christ as our personal Lord and Savior; no one else was qualified to pay the price for our sins but Jesus Christ, alone (John 14:6).