Any person who becomes "
born again" is just like physical birth. Babies do not know anything about the world in which they live. They are constantly falling down, and hurting themselves. No body is born a full grown man. The Bible describes in many places about growing in the Lord and in power of his might. Going from drinking milk to eating meat takes a long time. Some who have been saved for decades are still needing the milk of the word. Wisdom, which is understanding is essential to spiritual growth. How can a man cleanse his way?
Psa 119:9 BETH.
Wherewithal shall a young man cleanse his way? by taking heed thereto according to thy word.
I did not know anything about the Word of God when I was first saved. All I knew was
"Jesus loves me yes I know for the Bible tells me so"

It has taken many years of fellowship with God, and him teaching me his ways to get where I am now. Am I perfect? Nope. Do I sometimes stagger, and fall? Yep. No one is without sin in this life. Only Jesus could ever claim that, in fact Jesus said to one person, "
why are you calling me good, there is no one good except for God"
The Bible describes that "
if we would walk in the light as he is in the light we will have fellowship with one another and, the blood of Jesus will cleanse us from all sin"
That does not mean we don't have sin, it means God will cleanse us from sins we do not, have knowledge of!! Just in case we did not understand what he was saying, John in the next verse says.
"If we say we have no sin we deceive our self's, and the truth is not in us"
And then in the next verse John says, "
If we confess our sins, God is faithful and just to forgive us our sins, and then cleanse us from all unrighteousness"
When a Christian begins to grow it is because he is learning from God the Father about God himself. All understanding of the Word of God is about God who is the Word. Learning requires the person to do what he knows to do. If that person does not do what he knows is right that is sin to him.
James 4:17
Therefore to him that knoweth to do good, and doeth it not, to him it is sin.
When you do not do what is right you will know it. Your heart will condemn you, and that is when you need to confess your sin(s) to God. Christianity is a learning process. You can not do what you don't know.
The greater blessings are on those who know more, but, they also have the greater responsibility to do what they know!
This takes a life time to learn, and there will many falls, but thank God he knew this from the beginning!