The devil is a liar and has been deceiving people over the years by convincing them that they cannot be saved by God's grace alone but by their human good-works, accompanied by Faith.
If it was possible for a man to ever become perfect on earth on his own, Jesus need not have died on the cross, crushed and torn!
God knows that human beings can't meet His high standards and live a perfect life.
Adam is our forefather who sinned against God, and through him, sin affected the entire human race. We were sinners even when we were born.
The Old Testament way of receiving forgiveness for sins by offering a sacrifice of sheep was a shadow of the things to come. The Old Testament priests checked the perfection of the sacrificial lamb and not the sinner, and now, God sees His Perfect Son in us and does not consider our sins.
The commandments and the sacrificial system helped man realize that He is a sinner and is in desperate need of a Savior.
People in the old testament also received eternal salvation in the same way we do today, by believing in God's Word and that He would send a Messiah who would save them.
Jesus explained that we are incapable of turning sinless on our own and the rightful punishment that we deserve for our sins, in the Gospels, including the below.
Matthew 5:22 - But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hellfire.
Mark 9:43-48 - And if thy hand offend thee, cut it off; it is better that you enter into life maimed than having two hands to go into hell, into the fire that never shall be quenched:
The above verses are not teaching Self-Righteousness, as often misunderstood.
We can never turn sinless, but we can sin less. The penalty for our sins is very severe, and we do not qualify to pay it. Jesus paid it already. We can stand blameless in front of God, on the day of Judgement, only by wearing His Righteousness and not our own.
Isaiah 64:6 - But we are all as unclean thing, and all our righteousness are as filthy rags, and we all do fade as a leaf; and our iniquities, like the wind, have taken us away.
1 Corinthians 1:30- "But by His doing you are in Christ Jesus, who became to us wisdom from God, and righteousness, and sanctification, and redemption"
This Post: Saved by Faith or Faith plus Works?
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