We are reconciled to God by the death of Christ, and saved by His life. The life, which does this, is the life from which all created things came, and by which they exist. The power of redemption is the power of creation, and that is the power of the life of Christ. The Sabbath is a great memorial of the wonderful works of God, which are the measure of His graciousness. He gave it that we might know that He is the Lord that sanctifies us.
Ellet J. Waggoner
The Cross is the demonstration of the power of God and of the inability of man.
The Cross is not just a singular event that happened about 2000 years ago. Revelation 13.8 "the Lamb was slain from the foundation of the world."
At creation God breathed out the breath of life into man; at the cross, Jesus breathed out His endless life that we might breathe it in.
“Therefore I say to you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven men. Anyone who speaks a word against the Son of Man, it will be forgiven him; but whoever speaks against the Holy Spirit, it will not be forgiven him, either in this age or in the age to come.
Matthew 12.31, 32
And thus all the sin of this world, from its origin in the world to the end of it in the world, was laid upon Him: both sin as it is in itself and sin as it is when committed by us; sin in its tendency, and sin in the act; sin as it is hereditary in us, uncommitted by us, and sin as it is committed by us.
A correct understanding of the Covenants is vital to a correct understanding of the Gospel of Jesus. The new Covenant is God's one-way-promise to us whereas the Old Covenant is the people's promise to do only what God is capable of doing. This Old Covenant is worthless and leads to only death. Man cannot fulfill God's promise - only God can.
Many rebel against the idea that ALL must be received as a gift; our efforts do not contribute one iota towards our salvation.
It is not enough to confess that Jesus Christ did come in the flesh; that will bring no salvation to anybody. We must confess from positive knowledge that Jesus is just now come in the flesh, and then we are of God. Christ came in the flesh eighteen hundred years ago, just for the purpose of demonstrating the possibility.