"You have heard that it was said, 'Love your neighbor and hate your enemies.' But I say to you, love your enemies. Pray for those who hurt you. If you do this, you will be true children of your Father in heaven. He causes the sun to rise on good people and on evil people, and he sends rain to those who do right and to those who do wrong. If you love only the people who love you, you will get no reward. Even the tax collectors do that. And if you are nice only to your friends, you are no better than other people. Even those who don't know God are nice to their friends. So you must be perfect, just as your Father in heaven is perfect." Matthew 5:43-48
Does being holy mean being perfect?
Yes, and no.
Based on my own experience working with people over many years I have discovered one of the main things that keep people from being holy is the belief that they have to be perfect to be holy. Their efforts to be perfect prevent them from becoming holy.
Let me clarify. Holiness requires a perfection of desire but not a perfection of doing. Holiness comes as a result of perfect dependence upon the great work Christ did FOR US on the cross. His shed blood and the infilling of the Holy Spirit applies His perfect work to our hearts. Then it becomes incumbent upon us to walk in fellowship and obedience to God in the Spirit.
As Jesus taught in this portion of Scripture, holiness results from being filled with and motivated by the love of God and relating to others based on that love. So, you can unintentionally hurt or offend someone while trying to respond to them in loving ways, and be yet be perfect in your motive while imperfect in your execution of your faith.
God is most concerned with the desires and motives of your heart and mind. He is less concerned than with your execution or expression of those desires and motives.
What else could Jesus mean when He demands you to "be perfect as God is perfect"? God never sins or makes a mistake. You or I can never be perfect like that! So, if holiness is just about what we do we will never be perfect, and then Jesus is demanding something of us that is impossible for us. Why would He do that?
He wouldn't and He doesn't. He invites us to receive what He has provided through Jesus - the forgiveness of sins, the cleansing of the sin nature, and the filling of the Holy Spirit. Then He urges us to walk in obedience and in the power of His Spirit.
That is the perfection that is possible.
However, if you believe you have to "perfect" yourself in order to come to God for perfection, that effort to be perfect will prevent you from becoming holy.
You can never be perfect but you CAN be holy. But you can never become holy by trying to be perfect!