Dear AubreyM
This is the verse you quoted:
"If you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved." Romans 10:9
Then the very next verse says:
"For with the heart a person believes, resulting in RIGHTEOUSNESS, and with the mouth he confesses, resulting in SALVATION."
Righteousness is required (repentance of our sins):
"The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, BUT THAT ALL SHOULD COME TO REPENTANCE." 2 Peter 3:9
Sin Separates us from God
"Behold, the LORD'S hand is not shortened, that it cannot save; neither his ear heavy, that it cannot hear: BUT YOUR INIQUITIES HAVE SEPARATED YOU FROM YOUR GOD, and your sins have hidden his face from you, so that he will not hear." Isaiah 59:1, 2.
Jesus asked for repentance:
"From that time Jesus began to preach, and to say, Repent: for the kingdom of heaven is at hand." Matthew 4:17
Definition of repentance:
"The repentance (metanoia) called for throughout the Bible is a summons to a personal, absolute and ultimate unconditional surrender to God as Sovereign. Though it includes sorrow and regret, it is more than that. ... In repenting, one makes a complete change of direction (180° turn) toward God." (Wikipedia)
"To turn from sin and dedicate oneself to the amendment of one's life." (Merriam Webster. com)