It is customary that a boy approaching his bar-mitzva is taught the laws of tefillin. When Nisan approaches, one learns the laws of Pesach and before Tishrei, the laws of succahs. These are particular mitzvos, but teshuva is an all-embracing mitzvah which encompasses the entire Torah and the gamut of a Jew's whole life.
HaRav Leib Chasman once asked if the laws of teshuva are familiar to every Jew. Do we see anyone approaching a friend and asking that they study together the pertinent laws of teshuva?
It is common knowledge that there are three main components to teshuva: remorse, abandoning the sin and a resolution about the future. There is also confessing the sin, and they are all intertwined and interdependent. At times, a person stands before Hashem in purity, and yet, does not reach the point where he feels compelled to repent.
That is why he is told: Shuvah! Return!
A person who strays off the path will only get back on track when he realizes that he has drifted away and will not reach his destination if he perseveres. Therefore, every person must first realize that he is distancing himself and must not proceed along that path. This is the purpose of the call of "Shuvah" - get back on the right road; realize that you have wandered off and that your present path will only distance you from the goal for which you were created.
