Matthew 5:48
Be perfect, therefore, as your heavenly Father is perfect.
Hebrews 5:8-10
8. Although he was a son, he learned obedience from what he suffered
9. and, once made perfect, he became the source of eternal salvation for all who obey him
10. and was designated by God to be high priest in the order of Melchizedek.
HMmm.................
How about Peter's take on it?
2 Peter 1:5-12
5. For this very reason, make every effort to add to your faith goodness; and to goodness, knowledge;
6. and to knowledge, self-control; and to self-control, perseverance; and to perseverance, godliness;
7. and to godliness, brotherly kindness; and to brotherly kindness, love.
8. For if you possess these qualities in increasing measure, they will keep you from being ineffective and unproductive in your knowledge of our Lord Jesus Christ.
9. But if anyone does not have them, he is nearsighted and blind, and has forgotten that he has been cleansed from his past sins.
10. Therefore, my brothers, be all the more eager to make your calling and election sure. For if you do these things, you will never fall,
11. and you will receive a rich welcome into the eternal kingdom of our Lord and Savior Jesus Christ.
12. So I will always remind you of these things, even though you know them and are firmly established in the truth you now have.
2 Thessalonians 3:14-15
14. If anyone does not obey our instruction in this letter, take special note of him. Do not associate with him, in order that he may feel ashamed.
15. Yet do not regard him as an enemy, but warn him as a brother. (still a believer...)
1 Timothy 3:14-15
14. Although I hope to come to you soon, I am writing you these instructions so that,
15. if I am delayed, you will know how people ought to conduct themselves in God's household, which is the church of the living God, the pillar and foundation of the truth.
1 Corinthians 4:1-6
1. So then, men ought to regard us as servants of Christ and as those entrusted with the secret things of God.
2. Now it is required that those who have been given a trust must prove faithful.
3. I care very little if I am judged by you or by any human court; indeed, I do not even judge myself.
4. My conscience is clear, but that does not make me innocent. It is the Lord who judges me.
5. Therefore judge nothing before the appointed time; wait till the Lord comes. He will bring to light what is hidden in darkness and will expose the motives of men's hearts. At that time each will receive his praise from God.
6. Now, brothers, I have applied these things to myself and Apollos for your benefit, so that you may learn from us the meaning of the saying, "Do not go beyond what is written." Then you will not take pride in one man over against another.