The verb "sin" in the old testament is translated from the Hebrew word chatá. It's not what one thinks of when some speaks of sins. When the verb is used in a reflexive tense (meaning you are the cause) the Bible indicates sin is defined as missing the mark. As I read Isaiah, a familiar prophecy of Jesus stood out to me. Isaiah 53:12 ends with ...he was numbered with the transgressors; and he bare the sin of many, and made intercession, in Hebrew paga, for the transgressors. In the Greek, it is made up of two words but the root being tygchanō meaning to obtain. Whether you're reading in the old or new testament the definition doesn't change. Intercession, when used in the active tense, (indicating one's self as the cause) means to hit the mark. In Hebrews 7:25 it says of Jesus …he is able also to save them to the uttermost that come unto God by Him, seeing he ever liveth to make intercession for them. So, when sinning we miss the mark but, praise God, we have an advocate with the father, Jesus!
The apostle Paul said it this way in Romans 8:26 Likewise the Spirit also helpeth our infirmities: for we know not what we should pray for as we ought: but the Spirit itself maketh intercession for us…
So when you miss it, remember you can hit the mark, through Jesus...repent, have faith, and pray in the Spirit. You're gonna make it!