All the work of salvation is done by God himself.
The work of Jesus and his ministry, and his work of self sacrifice execution on the cross and resurrection.
The work of the Holy Spirit in the regenerate man. All the good works we see from a man is from the Holy Spirit, which are evidence of salvation, but not salvation it self.
So a re- examination of the fellow on the cross, shows faith granted by the Holy spirit resulting in repentance, and a work of the repented and regenerate man evidenced by another work of the the Holy Spirit, in the rebuke of the other criminal on the cross there along side.
the thief, with the confession of his mouth, showed that he believes Jesus is the Christ, the Son of the Living God, the Lord of heaven and earth -
he said, "Jesus, remember me when you come into your kingdom"
(Luke 23:42)
this doesn't come from man, but from God
“But what about you?” He asked. “Who do you say I am?”
Simon Peter answered, “You are the Messiah, the Son of the Living God.”
Jesus replied, “Blessed are you, Simon son of Jonah, for this was not revealed to you by flesh and blood, but by My Father in heaven."
(Matthew 16:15-17)
this knowledge of God -- it doesn't come through, from or by the flesh of anyone
No one knows the Son except the Father, and no one knows the Father
except the Son and those to whom the Son chooses to reveal Him.
(Matthew 11:27)
this knowledge - that the kingdom is Christ's, and that He goes to sit on the throne - that He is the Everlasting Father, having taken upon flesh - this is the rock upon which the church is built. the knowledge that He is the Christ, the Son of the Living God. and this knowledge, to know Him, is eternal life
this is eternal life: that they know You, the only true God, and Jesus Christ, whom You have sent.
(John 17:3)
this is salvation: to know Him: Yeshua, 'Yah is Salvation'
and this is a gift, not of works. no one can boast. no one knows Him except who He chooses to reveal Himself to -- and He is lifted up, just as the serpent in the wilderness, that we all may look to Him, and live!