Step one, lectio:  read the opening verses...

"'The word is near you; it is in your mouth and in your heart',

Step two, meditatio:  reflect on the verses...
First, a quick peek at the Greek lexicon. "Confess" is homologeo, and has the sense of agreement and celebration. "Word" is rhema (not logos!) and carries the sense of a message or discourse. "Believe" is pisteuo, a word used 264 times in the New Testament, particularly in the book of John. In addition to believing and professing, it has the sense of trusting.

Pisteuo is the crux of understanding this passage. In John 8:30-59, Jews who have believed in Jesus end up attempting to stone Him because of their unbelief [1]. So, pisteuo-belief can be lost. In Titus 1:16, the word pisteuo is translated "claim": "They claim to know God, but by their actions, they deny Him." So, whether a person is a believer is known from what they do. It is true that we are saved by faith and not by works; even the faith is not ours, but a gift from God (Eph. 2:8-9). But we don't know whether we are on the right track except through honest self-appraisal of our actions. Unless the self-appraisal is regular, we can go wrong and lose our belief.

A good image to understand the cycle of action and self-appraisal that saving faith requires is to compare God's light to a spotlight shining in darkness. The spotlight moves where it will, and unless we move with it, we enter the darkness.

If belief is flawless, then it continuously sustains and corrects itself: it is a re-birth. Jesus' belief was flawless, so He rose from His baptism complete. But human beings are not flawless. Many a baptized Christian does fall away and ends up denying Christ. Many others, like the Cretans Paul excoriates, claim Jesus with their lips and crucify Him by their actions. Preachers do a disservice to troubled people by telling them that they are assured of salvation if they only pray the Sinner's Prayer. While sincere confessional prayer can be saving, the commitment must be continuously renewed. The good news is that the better we know Jesus, the more we stay in the light and the more readily we return from error.

And that brings us to the final question: what does it mean to confess that Jesus is Lord? Just as Paul knew, by their actions, that the Cretans were deluding themselves in claiming to know Christ, our own actions speak loudly as to whether we believe or not. If we do not tell the truth, if we do not forgive, if we do not nurture, if we aren't prepared to suffer some inconvenience or harm to do what is right, then--no matter what we say or think-- we do not believe.

Step three, Oratio.  Pray from your newfound understanding...
Jesus, help us to know You. Faith is God's gift to us- we are by nature faithless. Love is also your gift to us. Help us to understand that we have no higher purpose than to serve as vessels from which Your light and love shine. Chide us when we claim your Name but behave unkindly. Don't let us turn a blind eye to wrong. Help us to understand that when we suffer for telling the truth, we take a blow that was aimed at you. Help us to trust you completely, so that we may truly believe, and believing, enter the Kingdom of Heaven.