Jesus said to him (Thomas), “I am the way, and the truth, and the life. No one comes to the Father except through me”. John 14:6
“For no one can lay a foundation other than that which is laid, which is Jesus Christ.” 1 Corinthians 3:11
For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things were created through him and for him.” Colossians 1:16
Only the one “by whom” and “for whom” all things were created could “take away the sin” that destroyed the first creation and bring in a “New Creation“.
There is only one KEY to open the Kingdom of Heaven for lost humanity. It is found in only four words “JESUS IS THE CHRIST“. He who was “in the beginning with God” and “was God” became a man to take away “the sin” that entered into the world through the first man Adam.
“You know that He appeared in order to take away sins, and in Him there is no sin. No one who abides in Him keeps on sinning.” 1 John 3:5-6
There are many Scriptures which show that because of the holiness of God there is only one way our Heavenly Father could restore humanity. Moreover, it would reveal the extent of His love for us. He was prepared to ask His only son to become a man, Jesus, to live a sinless life, so He could die in our place and thereby offer us redemption from our sins (our rebellion against God and His ways). Such a sacrifice on our behalf, and all our Heavenly Father requires of us, is to acknowledge and repent of our sins and embrace His son, Jesus, as our Saviour and Lord.
Jesus is the KEY to restore us, and once we repent and accept Him as our Lord and Saviour, our Heavenly Father sends the third person of the Trinity, The Holy Spirit to indwell our Spirit. We cannot be holy without the Holy Spirit, our body becomes the temple of the Holy Spirit. Notice that all three persons of the Trinity are involved in our Salvation.