The word repent is metanoeō and means have a change of mind. The Jews were called to have a change of mind on the basis of the Old Testament promises of the Kingdom and turn from their de-facto secularism so that they would be ready to receive their King. Christians are called to repent (have a change of mind) on the basis of the indwelling Spirit of truth.
The word "repent" in English carries with it much of the imagery of the Catholic sacrament of penance. It is often used as "feel real sorry", "try really hard to do better" or even "be punished". It carries a large measure of human effort of what could be called "the flesh".
There is a common view of the Christian life that we whip ourselves for failure as a prod on to make ourselves better or do good. This picture has too much "self" in it. The danger of the flesh is that we can end up like the Pharisees.
Luke 18:9-13 And he spake this parable unto certain which trusted in themselves that they were righteous, and despised others: Two men went up into the temple to pray; the one a Pharisee, and the other a publican. The Pharisee stood and prayed thus with himself, God, I thank thee, that I am not as other men are, extortioners, unjust, adulterers, or even as this publican. I fast twice in the week, I give tithes of all that I possess. And the publican, standing afar off, would not lift up so much as his eyes unto heaven, but smote upon his breast, saying, God be merciful to me a sinner.
I see God as less interested in our bringing our triumphs before him than our failures.
