"Sin" is transgression of Torah! (I John 3:4) The bottom line is, sin is sin, and that sin - no matter how great or small - is enough to separate us from God; and where in the Bible does God EVER say we are allowed to sin or that sinning is okay in certain circumstances?
There are really no degrees of sin. YHWH considers ALL sin something to keep us from Him, no matter how "great or small" we might think it is. That is why Adam and Eve were kicked out of the Garden of Eden for being guilty of just eating a piece of fruit from a tree YHWH said to stay away from - and mankind has been suffering, ever since!
The sons of Aaron were immediately put to DEATH by God for merely adding incense to the sacrifice to make it smell better (Leviticus 10:1, Numbers 3:4, Numbers 26:61). In the grand scheme of things, they were just trying to make the sacrifices smell better, which - while on the surface it seems it was no big deal, YHWH's death sentence revealed how grave disobedience to Him is! He gave us His Torah outlining how we are to act towards Him and to our fellow man, and He does not want us to deviate from this - especially in our worship of Him. These two above examples show how awful sin of ANY kind is! God makes no distinction when it comes to sin and Yeshua is all that stands between us and eternal death...
YHWH's grace and mercy were revealed by the fact that He did NOT kill Adam and Eve. Instead, He killed an innocent animal on their behalf and sent them on their merry way to live in a dangerous world. Why did He kill the sons of Aaron? Because they were cohens (priests) who should have known better than to mess with His ground rules about sacrifices!
Will He forgive a hungry man for stealing? Will He forgive the other one who doesn't need to steal but yet goes ahead and does it? We don't know; we are not God. He knows our hearts and our reasons, but this is exactly why He sent us His Son to be our FINAL SIN SACRIFICE/OFFERING - simply because He is merciful and obviously wanted to grant us an easier way to atone for our sins.
The thing is, God said DON'T STEAL, which means we do not have a right to steal, no matter WHAT our reasoning! Just like we don't have a right to ignore His commanded Seventh Day Sabbath or make up our own "holy days" and insist they're for God....
But for Yeshua's atoning death, we would ALL be headed for hell!
The bottom line is, man commits two types of sinning: Advertent and inadvertent - and the Bible tells us there is no sin sacrifice for willful, continued sinning:
Hebrews 10: 26 For if we deliberately continue to sin after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, 27 but only the terrifying prospect of Judgment, or raging fire that will consume the enemies.
The Bible tells us there is one unforgivable sin, and that is the "grieving of the Holy Spirit":
Ephesians 4: 30. And do not grieve the Ruach haKodesh of Elohim, whereby you are sealed for the day of redemption. (AENT)
FOOTNOTE: Proving that the Ruach haKodesh (Holy Spirit) is not a separate entity, but another title for YHWH.
Matthew 12: 32. And anyone who says a word against the Son of man, he will be forgiven, But anyone who will speak against the Ruach haKodesh....(AENT)
FOOTNOTE: If a person committed one of the capital offenses that are mentioned in Torah, but confessed and pleaded for forgiveness, there were ways to receive atonement. But those who blaspheme against the Spirit of YHWH have no way to make atonement for themselves, nor can they make an appeal in the name of Yeshua. See also Acts 5:1-11 and Hebrews 10:28-30.