The word conscience does not appear in scripture till the book of John when the Pharisees and scribes bring a woman who was caught in adultery to be stoned. Jesus simply said: He that is without sin to cast the first stone. They were convicted by their own conscience and left one by one until only the woman and Jesus was left standing. We learn that our conscience helps us to make the right decision, and Jesus further teaches that HE is the light sent to give us hope out of the darkness of this world. (John 8:7-9,12) So when they continued asking him, he lifted up himself, and said unto them, He that is without sin among you, let him first cast a stone at her. And again he stooped down, and wrote on the ground.And they which heard it, being convicted by their own conscience, went out one by one, beginning at the eldest, even unto the last: and Jesus was left alone, and the woman standing in the midst. Then spake Jesus again unto them, saying, I am the light of the world: he that followeth me shall not walk in darkness, but shall have the light of life….(John 3:19-21).
We are given a conscience to help us to see right from wrong, and we have heard it said when someone does something wrong that they need to grow a conscience to see their error in a matter. To those that are unbelievers their conscience is defiled by following a lie, and even though they profess they know God it is seen by their works HE is denied by them and therefore are considered to be disobedient. (Titus 1:15,16). Unto the pure all things are pure: but unto them that are defiled and unbelieving is nothing pure; but even their mind and conscience is defiled.They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate.
We are told to be happy through any suffering we endure for following righteousness, as there will be those who will speak evil of our good conversation in Christ. But we with a good conscience know it is never wrong to follow what is right in the eyes of God. (1 Peter 3:14-17). But and if ye suffer for righteousness’ sake, happy are ye: and be not afraid of their terror, neither be troubled; But sanctify the Lord God in your hearts: and be ready always to give an answer to every man that asketh you a reason of the hope that is in you with meekness and fear: Having a good conscience; that, whereas they speak evil of you, as of evildoers, they may be ashamed that falsely accuse your good conversation in Christ. For it is better, if the will of God be so, that ye suffer for well doing, than for evil doing.
Christ gave us the ultimate gift by shedding his blood at the cross which purges our conscience from dead works to serve the living God, as the New Testament given to us removes our sin! (Hebrews 9:13-15) For if the blood of bulls and of goats, and the ashes of an heifer sprinkling the unclean, sanctifieth to the purifying of the flesh: How much more shall the blood of Christ, who through the eternal Spirit offered himself without spot to God, purge your conscience from dead works to serve the living God? And for this cause he is the mediator of the new testament, that by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance….. (Matthew 26:28).