Numbers 15:22 on to the end of the chapter. Notice in this sacrifice there is a foreshadow of the Lord's supper of the grain and drink offerings. Also, notice that there was no sacrifice for presumptuous/willful sin. They killed them.
Also, 1 John 1:7 talks about walking in the Spirit. What type of sin can one commit while not in the flesh (Romans 8:9)? The type that the blood of Jesus keeps on cleansing.
Also, notice 1 John 2:1. Do you see any sign of needing to repent as you would if you committed a willful sin? No. These are the sins we commit while walking in the Spirit. Again, 1 John 1:7
1 John 1:6, 8 and 10 are about the Gnostics of 1 John 4:1-3 that did not believe sins of the flesh were even sins, so no need to confess them as admonished in verse 9. Verse 9 is how to become a Christian. Notice 6, 8 and 10 are not written about together as they would be in a Greek style of writing. No, this is a Semitic (Hebrew) style of writing opposites.
5 - God is light
7 - If you walk in the light
9 - Cleansing of all sin (receiving the Holy Spirit who does not sin Acts 2:38
6 - walk in darkness - no truth
7 - doesn't admit sin - no truth
10 - still doesn't admit sin - no truth