Jesus is the "because" and "therefore" of our salvation because He died for our sin
It isn't “what” Christians confess, but “Who” we confess that makes all the difference. What distinguishes Christians from other religions is the "Who" of our confession. As St. Paul writes in his letter to the Philippians (Phil 2:5-11), Christ Jesus is both the subject and object of our confession. Our Christian confession runs in the way of the Alpha and Omega, Christ alone as Lord and God. He is the "because" and "therefore" of the Church's proclamation. Because of what Jesus has done for us, even dying on a cross in our place—therefore we live, and move, and have our being in Him. Jesus died on a cross for us because He did not regard equality with God as something to be grasped tight, but instead made Himself a slave by pouring Himself out for our sin. Jesus "poured out his soul into death" (Isaiah 53:12). In the Old Testament way of confessing the Messiah, when Jesus "poured himself out" this is the same as saying, "his blood and soul poured out," which means "he died" even a "death on the cross."
Why would he do this for us? Because "the Son of Man came to serve and not to be served, and to give his life (soul) as a ransom for many" (Mark 10:45). Jesus "makes his soul an offering for our iniquities." "He was numbered with the transgressors." His death makes full atonement for the sin of the world.
By Jesus' bloody suffering and death for sin and His resurrection for our justification God proves that He runs all the verbs of salvation. Jesus is the "because" and "therefore" of our salvation because He died for our sin and therefore was raised for our justification. Likewise, when we are baptized into Christ we are baptized into His death so that just as Christ was raised from death to the glory of God the Father, we too may walk as new men.
Therefore, what makes the Christian confession of God so unique isn't the "what" of it at all, but the Who-ness of Jesus. Who Jesus is makes all the difference. Jesus is the Christ, the Lord and God, Whose name is the glory of God the Father. When we Christians confess Christ Jesus alone as our atoning sacrifice, as the one time for all time sacrifice for sin, as our total justification, then we are confessing our joy to the glory of God the Father, the only true worship of God, which hangs entirely on Jesus and what He's done for us.
To confess the name of "Jesus" is to say, "Our salvation is God's doing alone." Who Jesus is, along with the verbs of salvation that accompany His name, tells us (and the world) everything that is, and can be, and ever will be known about God, human beings, sin, life, and eternal salvation. Jesus is the One Who does the verbs of salvation to us today and always. All done for us, for free, by the God-man. Who Jesus is for us is the Alpha and Omega, the because and therefore, the beginning and end, the wellspring of our Christian confession. Because He has done it, salvation for us is complete. Therefore, all our thinking and speaking and doing as Christians runs in the way of Christ Jesus and His doing for us.