For there is one God and one intermediary between God and humanity, Christ Jesus, himself human (1 Timothy 2:5).
When we think of Jesus as an intermediary the first thing we think of is the fact he died for our sins. Paul calls Jesus our “Passover lamb” sacrificed for us (1 Corinthians 5:7). The Gospels of Matthew Mark and Luke all record the institution of the Lord’s supper. At that time Jesus made it clear his sacrifice constituted a new covenant in his blood (Matthew 26:26 – 29, Mark 14:22 – 25, Luke 22:17 – 20). His sacrifice provided for right relationship with God the Father and access to all of God’s promises.
Now, the reason this was necessary is because Adam, the first man, broke fellowship with God. Adam and Eve were told they would die if they disobeyed God and indeed they did. Their physical death happened many years after the event but spiritual separation from Yahweh was immediate. That is the curse of death – separation from God.
As the original covenant head of humanity, Adam’s sin brought every human being who came after him into conflict with God. Every person is born in a state of enmity with God. As a result, every person needs to be reconciled to the Father. No one is able to do this for themselves. Thus, the need for and intermediary, a substitutionary sacrifice.
This is the most obvious aspect of Jesus mediation between God and humanity. No one can live a perfect life. No one can present themselves as an adequate sacrifice for their own sins let alone for the sins of others. Nevertheless, God’s justice must be satisfied. A death sentence was pronounced upon humanity for the original sin of Adam and for the sinful nature every human being has inherited from that time forward. The only solution was to find a perfect “Adam” who would live a life in full compliance with God’s law; one who lived a life of perfect fellowship with the Father. Moreover, the requirement of participation without coercion was also present. In other words, the perfect sacrifice had to be willing to die for the sins of others. The appropriate intermediary is one who lays his life down by his own choice. In addition, the appropriate sacrifice had to be of infinite value. Billions of people have sinned against God and all of creation groans under a curse and requires reconciliation to the Father. Therefore, the only appropriate sacrifice is a perfect man, willing to die for others who is God himself - of infinite value able to cover the sins of all those who are saved and to repair the ravages of sin throughout the cosmos. Jesus, the last Adam, the Son of Man, the Eternal Son of God made flesh is the only one who meets these criteria.
Jesus of Nazareth, born of a woman, born under the law, the Eternal Son of God in human flesh willingly laid his life down to pay for the sins of his people and to heal sin battered creation. There is no other intermediary between God and humanity. Nor is there salvation in any other, for there is no other name under heaven given among men by which we must be saved (Acts 4:12).