If you declare with your mouth, “Jesus is Lord,” and believe in your heart that God raised him from the dead, you will be saved. Romans 10:9 NIV
What did Paul have in mind in Romans 10:9 when he associated confession of Jesus as Lord with salvation? Confessing Christ before government officials when martyrdom was on the line? Telling one’s family and neighbors that you believe in Jesus? Saying the words in private or to another Christian to “accept Christ”? However important these things may be, I don’t think that’s what Paul is thinking about here.
Romans 10:9 comes as part of a larger discussion of what it mean to be a part of the covenant community of Israel (chapters 9-11). In this context, I think Paul is using the word “confess” (“homologeo“) in a rather technical sense. “Jesus is Lord” (“kyrios iesous“) is an acclamation of faith, a simple liturgical form. Whether it was used in the church’s baptism ritual or in the weekly worship of the church, what I think we see in “kyrios iesous” is the church’s earliest formal confession of faith. It is the “Nicene Creed” or the “Apostles’ Creed” of the mid first century.
With the coming of Christ, the covenant community is now marked by its confession of Jesus as Lord and belief in the resurrection, and not the boundary markers of the Mosaic law. To see Romans 10:9 solely in terms of an individualistic transaction between the believer and the Lord is, I think, to misunderstand Paul at this point. To confess Jesus as Lord is to join in the common confession of the church at worship.