What is the context?
Paul opens with his calling as an apostle of Christ Jesus and names Sosthenes alongside him as a brother. He addresses the church as belonging to God. Before correcting its divisions and misconduct, he reminds its members who has called them and whom they belong to.
To be sanctified is to be made holy and devoted to God. The Greek verb is hagiazō (hah-gee-AH-zoh), ἁγιάζω; Thayer’s entry includes dedication to God and inward cleansing. Paul locates their holiness in Christ Jesus and calls them to a holy life. His later corrections show that this greeting does not mean their conduct is already faultless.
The greeting also reaches beyond Corinth to everyone everywhere who calls on Jesus Christ. He is their Lord and ours. The believers about to be corrected belong to a people much larger than their own congregation, and Paul begins by wishing them grace and peace from the Father and the Son.
How is this passage commonly understood?
Christians commonly read this greeting as grounding the church’s identity in God’s call and its relationship with Christ, with holiness as both a gift and a calling. The words about believers everywhere also place the local congregation within the wider people who belong to the same Lord.
Where does this fit in God's plan?
1 Peter 2:4–10 describes believers coming to Christ as living stones being built into a spiritual house. It calls them a holy people whose purpose includes declaring the goodness of the One who brought them out of darkness.
That wider picture helps explain why the church’s identity matters before Paul addresses its problems. God is forming a people who belong to Him and make His goodness known; the way they live together should reflect that calling.
What is our position?
We don't have a position on this passage yet. When our study reaches a conclusion the text supports, it will appear here.