1 Peter 1:15-16
but in your whole life show yourselves to be holy, after the pattern of the Holy One from whom you received your Call.
Matthew 5:48
You, then, must become perfect--as your heavenly Father is perfect.
2 Corinthians 6:14-16
Do not enter into inconsistent relations with those who reject the Faith. For what partnership can there be between righteousness and lawlessness? or what has light to do with darkness?
2 Corinthians 7:1
With these promises, dear friends, let us purify ourselves from everything that pollutes either body or spirit, and, in deepest reverence for God, aim at perfect holiness.