What have you understood repentance to be? Nearly everyone I have come across has a slightly different view, yet there are common understandings about repentance among Christians. This variation of belief is a natural process that comes out of the fact that no one is quite the same as the next person. So many of our real understandings come out of personal individual practical experience in relating with Jesus and our hunger to really know Him. Because of this there are some things that I have heard being taught as repentance that are not actually scriptural. 

(There are other articles on this website that intersect with repentant living such as " Totally Yielding To Jesus ", " Baptism in Water " and " Living after the Spirit ".)

The message

John the Baptist and Jesus preached and taught repentance both as a beginning to walking with God and as an essential foundation to continue walking with Him.
Mk 1:15 And saying, The time is fulfilled, and the kingdom of God is at hand: repent (have another mind), and believe the gospel (good news).
Matt 3:7,8,9 But seeing many of the Pharisees and Sadducees come to his baptism, he said to them, O generation of vipers, who has warned you to flee from the wrath to come? Bring forth therefore fruits worthy of repentance; and do not think to say within yourselves, We have Abraham as our father. For I say to you that God is able to raise up children to Abraham from these stones.

The disciples of Jesus carried on with this message.
Acts 26:20 But showed first to those in Damascus, and Jerusalem, and throughout all the country of Judea, and then to the nations, that they should repent (think differently) and turn to God (revert: turn about again), and do (practise) works (to work, act) worthy (deserving, suitable) of repentance (compunction, deep unease proceeding from a sense of guilt, sting of conscience).

How does it work?

To change your mind means to refocus in another direction. In this context, it is a change from old creature sin consciousness to New creature Jesus consciousness that is the turn we take. The result of that change of mind and attitude results in naturally doing life in a way that is empowered by Jesus righteousness. What we focus on internally is important.

Belief in Jesus, as He is (majestic and powerful God alive and well in you), is necessary in order for repentance to work.
Hebrews 11:6 But without faith it is impossible to please Him, for he who comes to God must believe that He is, and that He is a rewarder of those who diligently seek Him.
1 John 4:17 In this is our love made complete, that we may have boldness in the day of judgement, that as He is, so also we are in this world.

The living works (or miracles) that He did called attention to this message.  John 10:38 But if I do, though you do not believe me, believe the works so that you may know, and believe, that the Father is in me, and I in him.

And so the message of repentance has become a message also carried by Holy Spirit filled believers in Jesus Christ. Those who are working in living connection with Him, God the Holy Spirit, will do the living works and Holy Spirit will act on the hearts of people who see and who hear the good news of resurrection Life available now to bring them to repentance as a way of life.
John 14:29 And now I have told you before it happens, so that when it happens you might believe.
John 16:7-11 Nevertheless I tell you the truth; It is expedient for you that I go away: for if I do not go away, the Comforter will not come to you; but if I depart, I will send him to you. And when that One comes, he will convict the world concerning sin, and concerning righteousness, and concerning judgement: Concerning sin, because they do not believe on Me; Concerning righteousness, because I go to my Father, and you see me no more; Concerning judgement, because the ruler of this world is judged.

For Christians, motivation to turn to Him (repent) in a heart felt way comes through conviction that we have the righteousness of Jesus resident in us. Jesus taking up residence in us flows from belief in who Jesus really is and what He has done for us. The conviction or convincing comes from the work of the Holy Spirit in us. When Jesus walked the earth, the belief came most often from seeing the miraculous works of the Father and being with Him. Should it be the same for us? I most firmly believe so when I read Jesus commission to us and see "these signs shall follow alongside those who believe".

What does dead works mean to you? For me it is anything that I do that is not connected to Him. Making vows is another form of dead works and is not repentance.
So what is the essence of repentance? I have found that it simply means a decision turning around from what we want to do, to living works in all we do, by refocusing our inner (mind and heart) attention on Jesus who lives in us. When we maintain an inner focus on who He is inside us there is an activation of spirit (or new creature) inside us and living works and words flow out of us instead of the works and words centred in self agendas.

How do we know? The certainty of belief comes by Revelation from God directly to you in a personal way. This can be bible verses coming to life for you, someone’s words hit home, resonating strongly with your heart, or another source coming to life for you and producing conviction not condemnation.  It is important in all of this to stop the practice of beating ourselves up (condemnation) and to see that our Father is only interested in encouraging us to have another go at refocusing on Him, getting up and walking again, and that He has already dealt with the consequences. Changing our mind from beat up to having another try is part of repentance.

Detection and action

We can see at any time how we are going in living out repentance.  Here are Five levels and simple tests of manifested repentance.  We naturally grow through these as we spiritually grow and mature in our walk with Him.  These levels also reflect how much we are living out oneness with Jesus Life inside us.

1) doing my thing my way
2) doing my thing according to His ways
3) doing His thing my way
4) doing His thing according to my perception of His ways
5) doing His thing as He shows to. John 5:19

What is not repentance but is thought to be are things like Confession to a priest, penance, flagellation etc (OC attention on self based actions).  As we walk with our Father He will put attention on something that is tending to prevent us from growing in Him.  It can feel like He has put a spotlight on that area and we sometimes find it difficult to let go and let Him bring transformation and victory over that area of our life.
1 John 1:9 is talking about getting real with our Father when He puts the spotlight on and is written to those who are already children and experiencing the power of the blood of Jesus. If we admit to our sins (to our Father in heaven), He is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness. If we say that we have not sinned, we make Him a liar, and His Word is not revealed in us. 

If you are not a member of His Family by surrender to Jesus Christ then you are subject to the law of sin and death. If you are a member of His family, you are not subject to that law because God has paid the price for you, He has personally (in the person of Jesus Christ) removed all that can get in the way of relationship with Him. That means that you now have a Father-child relationship with Him and it is no longer a matter of SIN consciousness, but of a relationship where we can apologise to Him for our mistakes and move on, learning to live in a more and more harmonious way with Him because we want to, not because we have to.

Is repentance a relationship thing then? Yes in that context.
We learn to make the adjustment that what we do for Him out of self is iniquity or corruption and doesn't work well
We find out that only one is good. He is God and the only works we can call good are those He motivates and empowers
Therefore the only worthwhile works we can do are those He asks us to do and the only worthwhile way to do them is as we see from Him. 
Jesus modelled this for us for three and a half years.  His operational statement about it is 'I do what I see My Father doing and I speak out of what He is saying'. I have paraphrased it slightly to put it in modern english.  Jesus modelled this and said 'the things I do you will do also'.  If we wish to be effective in this, repentance living must be a way of life. 
Obedience is the key 1 Peter 2:21-25

Matthew 3:8 Bring forth therefore fruits worthy of repentance: Repentance itself is not visible to others but fruits of it are. The old creature mistake is to say that the fruits of repentance (of doing good works) are repentance.

Some more references for you to get the strength of it. Please look at these in context thoughtfully.

Mat 3:7 But seeing many of the Pharisees and Sadducees come to his baptism, he said to them, O generation of vipers, who has warned you to flee from the wrath to come?
Mat 3:8 Bring forth therefore fruits worthy of repentance; Mat 3:9 and do not think to say within yourselves, We have Abraham as our father. For I say to you that God is able to raise up children to Abraham from these stones.
Matthew 3:11 I indeed baptise you with water unto repentance: but he that comes after me is mightier than I, whose shoes I am not worthy to bear: he shall baptise you with the Holy Ghost, and with fire:
Matthew 9:13 But go ye and learn what that means, I will have mercy, and not sacrifice: for I am not come to call the righteous, but sinners to repentance.

Mark 1:4 John did baptise in the wilderness, and preach the baptism of repentance for the remission of sins.
Mark 2:17 When Jesus heard it, he saith unto them, They that are whole have no need of the physician, but they that are sick: I came not to call the righteous, but sinners to repentance.
Luke 3:3 And he came into all the country about Jordan, preaching the baptism of repentance for the remission of sins;
Luke 3:8 Bring forth therefore fruits worthy of repentance, and begin not to say within yourselves, We have Abraham to our father: for I say unto you, That God is able of these stones to raise up children unto Abraham. 

Luke 5:32 I came not to call the righteous, but sinners to repentance.
Luke 15:7 I say unto you, that likewise joy shall be in heaven over one sinner that repenteth, more than over ninety and nine just persons, which need no repentance.
Luke 24:47 And that repentance and remission of sins should be preached in his name among all nations, beginning at Jerusalem.
Acts 5:31 Him hath God exalted with his right hand to be a Prince and a Saviour, for to give repentance to Israel, and forgiveness of sins.

Acts 11:18 When they heard these things, they held their peace, and glorified God, saying, Then hath God also to the Gentiles granted repentance unto life.
Acts 13:24 When John had first preached before his coming the baptism of repentance to all the people of Israel.
Acts 19:4 Then said Paul, John verily baptised with the baptism of repentance, saying unto the people, that they should believe on him which should come after him, that is, on Christ Jesus.
Acts 20:21 Testifying both to the Jews, and also to the Greeks, repentance toward God, and faith toward our Lord Jesus Christ. 

Acts 26:20 But shewed first unto them of Damascus, and at Jerusalem, and throughout all the coasts of Judea, and then to the Gentiles, that they should repent and turn to God, and do works meet for repentance.
Romans 2:4  Or do you despise the riches of His kindness, and the forbearance and long-suffering, not knowing that the kindness of God leads you to repentance?
Romans 11:29 For the gifts and calling of God are without repentance.
2 Cor 7:9 Now I rejoice, not that ye were made sorry, but that ye sorrowed to repentance: for ye were made sorry after a godly manner, that ye might receive damage by us in nothing. 

2 Cor 7:10 For godly sorrow works repentance to salvation not to be repented of: but the sorrow of the world works death.
2 Tim 2:25 In meekness instructing those that oppose themselves; if God peradventure will give them repentance to the acknowledging of the truth;
Hebrews 6:1 Therefore leaving the principles of the doctrine of Christ, let us go on unto perfection; not laying again the foundation of repentance from dead works, and of faith toward God,
Hebrews 6:6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame. 

Hebrews 12:17 For ye know how that afterward, when he would have inherited the blessing, he was rejected: for he found no place of repentance, though he sought it carefully with tears.
2 Peter 3:9 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.