There seems to be some confusion as to what "perfect" means. I'd suggest you all make sure you're using the word the same way.
Our Lord does not expect perfection from us, He knows all would fail. That's why we needed Jesus! Oh, I know.
Matthew 5:48
48 But you are to be perfect, even as your Father in heaven is perfect.../NLT
I can link you to what the BLB says about Perfect. It says it's an adjective.
G5046 - τέλειος téleios, tel'-i-os; from ; complete (in various applications of labor, growth, mental and moral character, etc.); neuter (as noun, with ) completeness:—of full age, man, perfect.
www.blueletterbible.org
John 3:
5 Jesus replied, “I assure you, no one can enter the Kingdom of God without being born of water and the Spirit.[
b] 6 Humans can reproduce only human life, but the Holy Spirit gives birth to spiritual life.[
c] 7 So don’t be surprised when I say, ‘You[
d] must be born again.’ 8 The wind blows wherever it wants. Just as you can hear the wind but can’t tell where it comes from or where it is going, so you can’t explain how people are born of the Spirit.”.../NLT
We cry out to God to save us. He responds by giving us a new spirit. Apparently the Holy Spirit gives birth to our spiritual life (v. 6). I don't see how our new spirit can be imperfect? The Holy Spirit (GOD) does not give damaged gifts. So the Lord sees (Christ's) righteousness upon us in Christ, hence, our spirit is perfect. Sinless. Our conscience is (probably) the voice of our spirit. And he always tells us to do the right thing. The best thing.
Ok so, perfect spirit, not perfect soul or flesh body. We are told repeatedly in scripture, overcome the flesh. Deny the flesh. Feed your spirit. It is your spirit that gets his spiritual advice directly from the Holy Spirit.
Our carnal self is the other one that argues with you in your head and says, go ahead and do it, it'll be fun! Nobody will know...But if you exercise your spirit by listening to your own conscience and denying the flesh (fasting or whatever), it is possible to overcome the flesh and bring it into subjection to the Spirit. Be led by the Spirit, walk in the Spirit....
Receiving a wonderful new perfect spirit from the Lord is awesome. But it's also for us, the beginning of our walk with the Lord. What next? Read the word, pray look towards the spirit.
I don't see any holes in that.