1 Cor 1:2, Rom 11:16, Col 1:22, Heb 10:10, 14, Heb 13:12
God is holy. A holy God sanctifies us. (Lev 22:32)
Lev 22:32 Neither shall ye profane my holy name; but I will be hallowed among the children of Israel: I am the Lord which hallow you,
Jesus died on the cross to make us holy. (Col 1:22, Heb 10:10,14, Heb 13:12)
Col 1:22 In the body of his flesh through death, to present you holy and unblameable and unreproveable in his sight:
Heb 10:10 By the which will we are sanctified through the offering of the body of Jesus Christ once for all. 14 For by one offering he hath perfected for ever them that are sanctified.
Heb 13:12 Wherefore Jesus also, that he might sanctify the people with his own blood, suffered without the gate.
We who believe in Jesus Christ are made holy. That is why we are called 'saints'. (1 Corinthians 1:2)
1 Corinthians 1:2 Unto the church of God which is at Corinth, to them that are sanctified in Christ Jesus, called to be saints, with all that in every place call upon the name of Jesus Christ our Lord, both their's and our's:
Our root is Christ. So, because Christ is holy, we are holy. (Romans 11:16)
Romans 11:16 For if the firstfruit be holy, the lump is also holy: and if the root be holy, so are the branches.