Developing the spiritual tools necessary to become successful bringing other criminals to Christ involves a daily personal practice of prayer, devotion, and study.
We are fortunate—that with internet technology—the means of studying the great classics of the spiritual life is greatly enhanced; though the diversions implicit within the use of the internet are sometimes almost as destructive as the former is constructive.
One book I am currently reading, The Spiritual Life: A Treatise on Ascetical and Mystical Theology, by Aldolphe Tanquerey, S.S., D.D. (1854-1932) is available online and is described on the back cover of the paperback: “Published in English in 1930, The Spiritual Life by Fr. Adolphe Tanquerey has established a reputation as undoubtedly the finest, most comprehensive and best-respected one-volume treatise on the spiritual life ever published.”
Here is an excerpt:
“II. The consequences of the fall
“#69. Punishment followed quickly for our first parents and for their posterity.
“A) The personal sanction visited upon them is described in Genesis. Here again God's goodness is to the fore. He could have on the spot punished them with death. His mercy halted Him. He merely left them shorn of those special privileges with which He had vested them, that is, stripped of the gifts of integrity and of habitual grace. He did not touch their nature or the prerogatives flowing therefrom. Doubtless, man's will is weakened compared with the strength it possessed when integrity was his. However, there is no conclusive evidence that it is actually feebler than it would have been in a purely natural state, at any rate it remains free in choosing good or evil. God even condescended to leave our first parents in possession of faith and hope and gave their forlorn souls the hopeful assurance of a redeemer,--their own offspring, who would one day vanquish the devil and reinstatefallen humanity. By His actual grace, at the same time, He invited them to repentance, and as soon as they repented, He granted them pardon of their sin.
“#70. B) But what will be the condition of their descendants? The answer is that mankind will be likewise deprived of original justice, that is to say, of sanctifying grace and the gift of integrity. Those endowments, free gifts in every sense, a patrimony, so to speak, were to be handed to his heirs should Adam prove faithful. This condition unfulfilled, man comes into the world deprived of original justice. When through penance our first parents regained grace, it was no longer as a heritage for their posterity, but solely as a personal possession, a grant to a private individual. To the new Adam, Christ Jesus, who would in time become the head of mankind, was reserved the expiation of our faults and the institution of a sacrament of regeneration to transmit to each of the baptized the grace forfeited in Paradise.
“#71. Thus it is that the children of Adam are born into this world without original justice, that is, without sanctifying grace and the gift of integrity. The lack of this grace is called original sin, sin only in the broad sense of the term, for it implies no guilty act on our part, but simply a fallen condition. It constitutes, considering the supernatural destiny to which we are called, a privation of a quality that should be ours,--a blemish, a moral taint that places us out of the pale of God's kingdom.” (highlighting added)