From mesos (middle). A mediator — one who stands between two parties to reconcile them or to guarantee an agreement. Used exclusively of Moses and Christ in the New Testament. Christ is declared the mediator of a new and better covenant.
This is one of the most significant Christological terms in the New Testament. Paul declares there is 'one mediator between God and mankind, the man Christ Jesus' (1 Timothy 2:5). Hebrews develops this extensively: Jesus is the mediator of a better covenant (Hebrews 8:6, 9:15, 12:24). Unlike Moses, who mediated the old covenant that could not save, Christ mediates an eternal covenant sealed by His own blood. This word affirms that access to God comes only through Christ.