What exactly is repentance?  Why is it so important?  Are the terms repent and repentance the same or are they different?
1. What Repent Means…
The Greek word for repent in the New Testament is “metanoeo” which means “to change one’s mind” and this involves a turning from sin with contrition to God.  It’s like you headed out for a drive down the freeway but you went down the wrong way and were now headed in the wrong lane and the traffic was now coming straight at you. You need to turn around and go the other way. That is what repent basically means.
You are headed down the wrong way…..the way to hell…and you need to change your mind and turn around and go the other way. That is what it means to repent
2.What Repentance Means…
In the New Testament the same word used for repent (metanoeo) is essentially the same for repentance (metanoia) where one isa verb and one is a noun. A person is said to need to repent (metanoeo) and then they show repentance (metanoia). There are two words for repentance in the Old Testament Hebrew.  One word is “nacham” which means “to be sorry” or “to regret” but the overwhelming majority of the time it is used (391 times) it means “turn” or “return” (“shuwb”). Repentance occurs after a person decided that they need to repent.  It would be like someone wants to take a vacation and then they do and are then vacationing; one plans a vacation (noun) and when they do, they are vacationing (verb) so there is a time when a person choses to repent (noun) and when they finally do there is repentance(verb). If we realize that a noun is a person, place, or thing then to repent is a thing someone can do. The verb is the action of doing something. When someone decides that they need to repent (noun) then they fall on their knees and “change their mind and turn around or away from sin” (verb).
Many get confused over what repentance really is but let me say what it is not and what it often gets confused with.  Repentance is not apologizing, confessing, or being sorry for getting caught.  That is worldly sorrow and that is not the same as Godly repentance which is what Paul wrote about in 2 Corinthians 7:10-11“For godly grief produces a repentance that leads to salvation without regret, whereas worldly grief produces death.
For see what earnestness this godly grief has produced in you, but also what eagerness to clear yourselves.” Godly sorrow is what leads to a person not only confessing their sins but repenting of (changing one’s mind about) sins.  It is not regretting your sins, feeling bad over them, or feeling guilty about them.  Godly sorrow causes a person to turn away from or change their minds and go the other way. Paul says that a worldly grief or sorry leads to or produces death because there is no change of mind, no change of heart or no change of direction, going the other way and forsakings in and without godly repentance there is death…eternal death because there is no conversion of the human heart.
Repentance involves recognizing that you have thought wrongly in the past and determining to think rightly in the future. The repentant person has “second thoughts” about the mindset he formerly embraced. There is a change of disposition and a new way of thinking about God, about sin, about holiness, and about doing God’s will. True repentance is prompted by “godly sorrow,” and it “leads to salvation” (2 Corinthians7:10).
Repentance in the Bible….
In a Biblical context, repentance is recognizing that our sin is offensive to God. Repentance can be shallow, such as the remorse we feel because of fear of punishment (like Cain) or it can be deep, such as realizing how much our sins cost Jesus Christ and how his saving grace washes us clean (like the conversion of Paul).
Repentance and Salvation….
Repentance is an essential part of salvation, requiring a turning away from the sin-ruled life to a life characterized by obedience to God. The Holy Spirit leads a person to repent, but repentance itself cannot be seen as a “good work” that adds to our salvation
The Bible states that people are saved by faith alone (Ephesians 2:8-9). However, there can be no faith in Christ without repentance and no repentance without faith. The two are inseparable Repentance and faith can be understood as two sides of the same coin. It is impossible to place your faith in Jesus Christ as the Savior without first changing your mind about your sin and about who Jesus is and what He has done. Whether it is repentance from willful rejection or repentance from ignorance or disinterest, it is a change of mind. Biblical repentance, in relation to salvation, is changing your mind from rejection of Christ to faith in Christ.
While repentance is not a work that earns salvation, repentance unto salvation does result in works! It is impossible to truly change your mind without that causing a change in action. In the Bible, repentance results in a change in behavior. That is why John the Baptist called people to “produce fruit in keeping with repentance” (Matthew 3:8).
A person who has truly repented of his sin and exercised faith in Christ will give evidence of a changed life (2 Corinthians 5:17; Galatians 5:19–23; James 2:14–26)!!
What does it mean to Repent?…
I meet so many people today who are scared of that word. In fact, they’re so scared of it that they avoid using it altogether! Yet, very few actually understand what that little word means.
You may be surprised to learn the word repent in the Greek New Testament simply means to turn around. It was a military term that described a soldier marching in one direction and then doing an about-face. And when it’s used in a spiritual sense, it means to change your mind. So really, repent is a perfect description of what happens when you come to Christ. You no longer reject Christ, but now you believe that Jesus Christ is the Son of the living God. You do a spiritual about-face, which in turn changes everything. And not only do you change your mind about Christ, but you change your mind about sin as well as you discover what it really means to honor God. You realize that it’s no longer about performance. It’s about a heart attitude that confesses Christ and seeks to honor Him in every aspect of life! So should you be afraid of the word repent? No! Instead, embrace the idea of doing a spiritual about-face, turning to Christ and away from sin in your life!! To see what repentance looks like in real life, all we need to do is turn to the story of Zacchaeus. Here was a man who cheated and stole and lived lavishly on his ill-gotten gains—until he met Jesus. At that point he had a radical change of mind: “Look, Lord!” said Zacchaeus. “Here and now I give half of my possessions to the poor, and if I have cheated anybody out of anything, I will pay back four times the amount” (Luke 19:8). Jesus happily proclaimed that salvation had come to Zacchaeus’s house, and that even the tax collector was now “a son of Abraham” (verse 9)—a reference to Zacchaeus’s faith. The cheat became a philanthropist; the thief made restitution. That’s repentance, coupled with faith in Christ.
Repentance, properly defined, is necessary for salvation. Biblical repentance is changing your mind about your sin —no longer is sin something to toy with; itis something to be forsaken as we “flee from the coming wrath” (Matthew 3:7). It is also changing your mind about Jesus Christ— no longer is He to be mocked, discounted, or ignored; He is the Savior to be clung to; He is the Lord to be worshiped and adored. When you come to the New Testament there is one word you need to know — the Greek word metanoia, which literally means “to change the mind.” Repentance fundamentally means to change your mind about something. It has to do with the way you think about something. You’ve been thinking one way, but now you think the opposite way. That’s repentance — the changing of the mind!
Let’s suppose a man wants to learn how to parachute. So he goes to a parachute school and they show him how to rig up his gear, how to pull the rip cord, and how to land safely. Finally the day comes when they take him up in an airplane. He’s  scared to death but he’s afraid to back out. The moment comes when he is to jump. He goes to the door of the airplane and sees the ground 7,000 feet below. His legs grow weak, he’s about to throw up, and somebody behind him is trying to push him out of the airplane. At the last second he says, “No. I’m not going to do it.” “Go ahead, you can do it,” his instructor shouts. “I’ve changed my mind,” he replies. “I’m not going to jump.” And he doesn’t. That man has repented. He’s changed his mind in a decisive way. That story illustrates how repentance works. Repentance is a change in the way I think that leads to change in the way I live. When you really change your mind about something, it’s  going to change the way you think about it, talk about it, feel about it, and act about it. I’ m suggesting that true repentance is more than just a mental game. Repentance is a decisive change in direction. It’s  a change of mind that leads to a change of thinking that leads to a change of attitude that leads to a change of feeling that leads to a change of values that leads to a change in the way you live!!
Everything we said so far can be boiled down to three points:
1. Repentance is agreeing with and turning to God (while turning away from sin and your own efforts to save yourself)
2. It is absolutely necessary for salvation, for you must go to God to be saved.
3.It is the other side of the coin of faith: whenever there is genuine faith, there is genuine repentance as well.