The Rom 10:9 verse you quote is in the future tense. But you interpret it in the present (why am I not surprised!). This is the problem with non-Apostolic assemblies: everyone picks and chooses the verses that suit their particular brand of faith, their own personal version of Christ, their own private definitions and private interpretations, etc.
Consider then "but he that endureth to the end shall be saved" (Mat 10:22)
Salvation is something that has not yet occurred. Accepting Christ as your Savior is only the beginning of the process of salvation. It is a ticket...and it's up to you to jump on that train and stay on course until the end, living the faith (and that is more than going to bible reading every Sunday).
Baptists accept Christ and say they are instantly saved. And Luther basically said, "Praise the Lord, let it all hang out." You guys never cease to amaze me.
Regeneration produces a godly sorrow that grieves when we sin. We are aware of our sin and are quickened to mortify it. Of course, people backslide and become lazy in their sanctification, but that is due to a lack of obedience, not necessarily a lack of faith.
To accept what you believe, one would have to ignore Exekiel 36:25-27
"I will sprinkle clean water on you, and you shall be clean from all your uncleannesses, and from all your idols I will cleanse you. And I will give you a new heart, and a new spirit I will put within you. And I will remove the heart of stone from your flesh and give you a heart of flesh. And I will put my Spirit within you, and cause you to walk in my statutes and be careful to obey my rules." He does it, we don't. Dead men cannot choose life.
I was explaining how candidates for membership in my church evidence their faith. One method is a statement of faith. Then I said this "seems to be consistent with".... The timing issue is irrelevant since we believe salvation is a single event. Repeating "the event" is evidence that it has occurred, although it does not "re-save".