Here is another reference to the concept of learning how to adjust our character traits according to our inclinations, both good and bad...
http://www.nachalnovea.com/breslovcenter/articles/article_point2.html
The Righteous, the Wicked, and the Intermediate:
All Have the Same Potential
That seed, the good point hidden in one's soul, can raise a person to extraordinary heights. However, on the other hand, if it is improperly used, precisely the opposite can occur. All that amazing potential will become an impediment. Those same strengths will fall into the service of the Other Side, and a person will stumble in the area of his greatest ability. Instead of using his strengths to serve God, he offers them as a sacrifice to idols.
Thus the Talmud says: "A person born under the constellation of Mars will be inclined to bloodshed: either he will be a murderer, a butcher or a mohel (an expert in performing ritual circumcision)."[14] The Talmud is alluding to three groups: the righteous, the wicked, and the intermediate. If, G-d forbid, this person's good point falls into the hands of the Other Side, the person will become a murderer. If he actualizes his potential in a mundane way (neither holy nor profane), he will become a butcher (because in general, eating meat is neither a mitzvah nor a sin). However, if he can completely purify himself and turn his desire for bloodshed against his own evil inclination, he will become a mohel and sanctify his potential by using it for the performance of a mitzvah.[15]
Success is Hidden Where the Evil is Strongest
This is true of all our negative traits. The greatest potential for good lies hidden within the most overwhelming proclivity for evil. If a person can defeat his evil inclination, he becomes a tzaddik; if not, he may lose everything. The desires that attack a person on the path to God are the negative aspects of the very strengths he is working to refine.
"Before any Jew can attain a new level in Torah and avodah (Divine service)," Rabbi Nachman wrote, "he is first tried and refined in the exile of one of the 'Seventy Languages.' That is, in their evil desires... because the shell always precedes the fruit. Whoever wants to eat the fruit must first break the shell."[16] By breaking the shell, one raises oneself to God; if not, the potential remains in exile. Although in many ways, the shell resembles the fruit, it is its complete opposite.
The same is true of the path to self-perfection. Pride is an impure character trait. However, on the side of holiness, it can be transformed into a sublime appreciation of God's greatness. Immoral desires are impure but, in the realm of holiness, one can uplift them into a consuming love and longing for the Almighty. Cruelty is impure yet, at times, one must be cruel towards one's own evil inclination. There are many similar examples.
Rabbi Yaakov Yosef of Polnoye commented: "If a person is uncertain as to how he can best serve God, let him examine his basest desires and make use of them. Thus, we can explain the verse: 'You shall take My offering from every man whose heart moves him' (Exodus 25:2). That is, from the longings of the heart - the desires of this world - take God's offering. It is precisely this that elevates a person in the service of God."[17]
The Seed Hidden in the Ground
We must never become upset if negative desires at times overwhelm us, because the moment they attack is the moment they can be repaired. The verse says: "What does the Lord, your God, ask from you…" (Deuteronomy 10:12). From you - not from someone else. None of life's trials are arbitrary. God arranges them all to purify our souls and to bring us to our ultimate good: the revelation of our own unique point. This is like planting a seed. Before it can draw upon the power of the earth, it first must decay. Only then is its inner potential revealed, to sprout forth, with God's help, and reveal its inner beauty. The same holds true for each of us. Only when we have been chafed and worn away by the trials of this world do our unique strengths become revealed. Ultimately, the difficulties are for our eternal benefit.
These ideas are all hinted in Rabbi Nachman's amazing story about the prince made from precious gems.[18] In this story, a certain righteous man predicts that the king will have a son made up entirely of precious stones. The king does have a son, who proves to be an exceptional child, but nevertheless, only flesh and blood. At the end of the story, because of the schemes of his enemies, the young prince contracts leprosy. Yet when his skin dries up and falls away, the precious stones beneath the surface are revealed.