From Spiritual Insights Into an Essential Encounter with God by Fr. Donald Haggerty
Example of St. Peter: As he walked by the Sea of Galilee, he saw two brothers, Simon, who is called Peter, and Andrew his brother, casting a net into the sea—for they were fishermen. And he said to them, “Follow me, and I will make you fish for people.” Immediately they left their nets and followed him. As he went from there, he saw two other brothers, James son of Zebedee and his brother John, in the boat with their father Zebedee, mending their nets, and he called them. Immediately they left the boat and their father, and followed him” (Mt 4:18-22).

“The call to abandon a previous life, dropping everything at once to follow Our Lord on an itinerant, unknown journey, is the summons heard by Peter and Andrew, James and John, at the Sea of Galilee. A conversion in this case does not mean that a bad life has been left behind, a parting with evil ways. The conversion here involves a radical “yes” of personal fidelity to Jesus. The act overturns everything familiar and instantly attaches a life in a unique bond with Jesus Christ. The apostles all underwent such a conversion. The response did not make them immediate heroes or full of wisdom, zeal, and courage. It did place them for the next three years in constant proximity to Jesus. That closeness to him allowed the drawing power of his attraction to permeate their souls. Every person who goes far in a love for God and for souls will experience a similar pattern. The effect of following Our Lord after a very decisive choice for him, staying close to him especially in prayer, permits his presence to deepen its personal impact upon our life. A lifetime of spiritual need for God has its seeds in this initial period of conversion” (9).
Example of James and John: “There is another type of conversion anticipated in certain Gospel scenes, and this, too, is worthy of our pondering. Jesus offers challenges in the Gospel that will take time before they are understood in their deeper significance. When James and John requested seats on the right and left of Our Lord in his kingdom, they were told that they did not know what they were asking. “Are you able to drink the chalice that I drink?” (Mk 10:38). This form of conversion is always linked to some greater insight into the Passion of Christ. We realize that the Passion of Christ has entered mysteriously into our own life as a question—how far we are willing to go in love for him? The admonition that we must die to self for greater love is not just a spiritual metaphor. In fact, it is a direct challenge issued on the night before Jesus’ own crucifixion. “Will you lay down your life for me?” (Jn 13:38). To the degree we seek God with more intense love, we are on a path of confrontation with this question of dying for love of Christ. At some point long after an initial conversion, another leap of soul is necessary. A decisive “yes” to Our Lord is demanded, as it was earlier in life, but from a deeper layer of soul, overcoming any barrier of hesitation. Spiritual conversions of this kind may be the most important acts in our life. Crossing a threshold to an interior offering of all to God can lead to the gift of our entire life to him. Every saint in the course of a life underwent conversions of this type” (10-11).