If trying to disprove an all-encompassing statement, there are multiple ways to go about this. One: a contrary rule can be show to be true. Two: a specific contrary example can be given. Three: a contrary fact can be shown.
When Christians claim that “all sins are equal”, they are declaring a all-encompassing statement that is not found in the Bible. They usually mean by saying this that a sin is a sin. Stealing a pack of gum is the same level of sin as killing a baby. This is not a doctrine found in the Bible. Luckily the Bible contradicts this statement using all methods discussed above.
Jesus indicated that there were different levels of sins. Jesus said to Pilate that those who delivered Jesus to Pilate had the greater sin:
Joh 19:10 Then saith Pilate unto him, Speakest thou not unto me? knowest thou not that I have power to crucify thee, and have power to release thee?
Joh 19:11 Jesus answered, Thou couldest have no power at all against me, except it were given thee from above: therefore he that delivered me unto thee hath the greater sin.
Jesus is saying because government power is delegated to Caesar through the government and delegated to Pilot, the people who are acting under their own powers are more guilty. They have the greater sin. Elsewhere Jesus says:
Luk 12:47 And that servant, which knew his lord’s will, and prepared not himself, neither did according to his will, shall be beaten with many stripes.
Luk 12:48 But he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes. For unto whomsoever much is given, of him shall be much required: and to whom men have committed much, of him they will ask the more.
To whom much has be given (in knowledge), the greater his judgement. This is also consistent with the teachings of James:
Jas 3:1 My brethren, be not many masters, knowing that we shall receive the greater condemnation.
Masters here means “teachers”. The more you know the more you will be judged by a stricter standard. If a child steals a pack of gum, it is not the same as a police officer stealing a pack of gum.
Again showing not all sins are equal, Jesus also stated there was a special sin known as the unpardonable sin:
Mat 12:31 Wherefore I [Jesus] say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men.
Jesus here is distinguishing between most sins and a special sin. Everything can be forgiven except one. If all sins were equal, there could be no such thing as an unpardonable sin. They would either be all pardonable or all unpardonable.
So Jesus lays of a general rule, that people are judged unequally based on what they have been given. Jesus then cites a specific example, the Jews who handed Jesus over to Pilate having the greater sin. He then explains a specific sin treated differently then all the others, the unpardonable sin. Did Jesus think all sins were equal? It is obvious he did not, so then where do people get this idea?
Jesus in his sermon on the mount talks about “thinking a sin” and “doing a sin”. He covers several sins including murder and adultery:
Mat 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 hell fire.
Mat 5:27 Ye have heard that it was said by them of old time, Thou shalt not commit adultery:
Mat 5:28 But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
So is Jesus saying that all sins are equal or that all sins lead to hell? These are different concepts. As we have shown earlier, some will be judged with many stripes and some with few. Lusting after a woman in your heart, while it is adultery, is less of a sin then actually committing it. Calling your brother fool, is different than murder. Though all sins lead to separation from God, not all sins are equal.