When we are in the world we are sinners,although we can do good,but not entirely,and we can never fulfill God's law of love,which love is the fulfilling of the law.
When we confess Christ and repent of our sins truthfully,then all our sins are forgiven and not on our record,because the blood of Christ washes all those sins away.Then when we receive the Spirit we allow the Spirit to lead us to maintain that position,but we still have the capacity to sin if we desire to sin,but if we allow the Spirit to lead us we will act like Christ.
If we sin after we are saved,if we repent of it we will be forgiven for it.
The sins we repented of to be saved,we need not repent of those sins ever again,for all the past is forgiven,and all we have to do is repent of any sin we do after we are saved.If we live in sin and do not give it up,it is on our record and not forgiven,until we mean it to repent of it and not want it anymore.
The Bible says a Spirit led life is not under the law,which means if you are led of the Spirit you will act like Christ,therefore the law cannot touch you for prosecution,but if you sin you are back under the law,and if repented of that sin,and back to the Spirit leading you,you are not under the law again,but if you live in sin and will not give it up,you are back under the law,until it is repented of that sin and led of the Spirit again.
We confess Christ and repent of our sins,all sins are forgiven and off our record,there is no sins prior to that time on our record,and we never have to repent of those sins again,and we allow the Spirit to lead us,and if we sin we repent of that individual sin and it is forgiven.