It is possible to commit a sin against God unintentionally.  Even when this happens, we are still responsible for our unintentional conduct.  Consider what is found in Leviticus 4 and 5…

Lev 4:1 And the Lord spoke to Moses, saying, 2 “Speak to the people of Israel, saying, If anyone sins unintentionally in any of the Lord’s commandments about things not to be done, and does any one of them…

Lev 4:13 If the whole congregation of Israel sins unintentionally and the thing is hidden from the eyes of the assembly, and they do any one of the things that by the Lord’s commandments ought not to be done, and they realize their guilt,  14  when the sin which they have committed becomes known…

Lev 4:22 When a leader sins, doing unintentionally any one of all the things that by the commandments of the Lord his God ought not to be done, and realizes his guilt, 23 or the sin which he has committed is made known to him…

Lev 4:27 If anyone of the common people sins unintentionally in doing any one of the things that by the Lord’s commandments ought not to be done, and realizes his guilt, 28  or the sin which he has committed is made known to him

Lev 5:15 If anyone commits a breach of faith and sins unintentionally in any of the holy things of the Lord, he shall bring to the Lord as his compensation…

Lev 5:17 If anyone sins, doing any of the things that by the Lord’s commandments ought not to be done, though he did not know it, then realizes his guilt, he shall bear his iniquity.

It is possible for anyone (Priest, Leader, Congregation {group}, the average person) to sin and not mean to do it.  The responsibility is heightened when they “realize” they have sinned.  At that point… in each passage… the guilty party is to offer a sacrifice to God for their sin.

The one that made the largest impression on me was Lev 4:27-28… “Or the sin which he has committed IS MADE KNOWN TO HIM.”  It is important for the community of faith to help one another combat and overcome sin.  Our sin nature is so deceitful that we do and say things that are transgressions of God’s Law without knowing it!  We (I!) need people to help me realize when I have sinned, so that I can repent and confess it so as to walk more closely with God.  Plus there might be the need to reconcile with the one I sinned against!

So what do we do?  Consider the following…

Ps 139:23 Search me, O God, and know my heart! Try me and know my thoughts!  24 And see if there be any grievous way in me, and lead me in the way everlasting!

2 Cor 13:5 Examine yourselves, to see whether you are in the faith. Test yourselves. Or do you not realize this about yourselves, that Jesus Christ is in you?—unless indeed you fail to meet the test!

Ps 26:2 Prove me, O Lord, and try me; test my heart and my mind.

Pr 17:3 The crucible is for silver, and the furnace is for gold, and the Lord tests hearts.

Job 13:23 How many are my iniquities and my sins?  Make me know my transgression and my sin.

Job 34:32 Teach me what I do not see; if I have done iniquity, I will do it no more’

Ps 19:12 Who can discern his errors?  Declare me innocent from hidden faults. 13  Keep back your servant also from presumptuous sins; let them not have dominion over me!

Pr 4:23 Keep your heart with all vigilance, for from it flow the springs of life.

Lam 3:40 Let us test and examine our ways, and return to the Lord!  (Those 5 words are the key)