From Paul, called by God's will to be an apostle of Jesus Christ, and from Sosthenes our brother.
References for 1 Corinthians 1:1
To God's church that is in Corinth: To those who have been made holy to God in Christ Jesus, who are called to be God's people. Together with all those who call upon the name of our Lord Jesus Christ in every place— he's their Lord and ours!
Grace to you and peace from God our Father and the Lord Jesus Christ.
I thank my God always for you, because of God's grace that was given to you in Christ Jesus.
References for 1 Corinthians 1:4
That is, you were made rich through him in everything: in all your communication and every kind of knowledge,
in the same way that the testimony about Christ was confirmed with you.
The result is that you aren't missing any spiritual gift while you wait for our Lord Jesus Christ to be revealed.
He will also confirm your testimony about Christ until the end so that you will be blameless on the day of our Lord Jesus Christ.
God is faithful, and you were called by him to partnership with his Son, Jesus Christ our Lord.