A lot of people say "I'm sorry," but not everyone means what he or she says. True sorrow isn't simply a change in emotion – it's also a change in behavior. As Ezra confronted the sin of the Israelites (which happened to be marrying foreign women this time… a sin that Christians are guilty of when they marry non-Christians), the people came to terms with what they had done and how they had disobeyed the Lord. As God's people, they had a responsibility to seek to live in a way that pleased Him, but this was a clear violation of His commands. And so in brokenness they went to Him and pleaded; they confessed their sin, and they wept. Pay close attention to what happened next: they separated themselves from their sin. They turned away from it. They put away their foreign wives and children (presumably they did provide for them) and lived with them no more. AW Tozer addressed this issue of repentance in his book, The Pursuit of Man. I love what he said:
The truest and most acceptable repentance is to reverse the acts and attitudes of which we repent. A thousand years of remorse over a wrong act would not please God as much as a change of conduct and a reformed life.