Often when an individual converts to Christianity or experiences a spiritual renewal, they will want to set out immediately to change their lives. This is not a bad desire and can often lead to many good things.
However, there exists a temptation for converts to become overzealous, or try to overcompensate for their past sins and make radical choices that can threaten the foundation of their faith.
St. John Henry Newman explains in a sermon, "I observe, then, that repentant sinners are often impatient to put themselves upon some new line of action, or to adopt some particular rule of life. They feel that what they have done in time past is, as far as this life is concerned, indelible, and places an impassable barrier between themselves and others: happy only if that badge of guilt and shame does not outlast the grave, but is wiped out in the day of account."
This impatience can easily lead to choices that could potentially set them back or even revert to their former way of life.
Newman continues, "When men are in horror and anguish at their past sins, they are anxious to put some burden on themselves, which may relieve their feelings, and remind them of what they have been, what they are. Now nothing is more unadvisable in most cases than to begin with severity. Persons do not know what they can bear, and what they cannot, till they have tried it. They think almost they can live without food, without rest, without the conveniences of life to which they are accustomed. Then when they find they cannot, they despond and are miserable, or fall back, and a reaction ensues."
It is much better to gradually ascend the steps of sanctity, then try to fly when you do not have any wings. Instead of moving rapidly along the path of conversion, the individual will fall flat on their face and may be tempted to return to their former state of life.
Instead, Newman advises a zealous convert, "When men are in the first fervor of penitence, they should be careful not to act on their own private judgment, and without proper advice. Not only in forming lasting engagements, but in all they do, they need a calmer guidance than their own. They cannot manage themselves; they must be guided by others; the neglect of this simple and natural rule leads to very evil consequences. We should all of us be saved a great deal of suffering of various kinds, if we could but persuade ourselves, that we are not the best judges, whether of our own condition, or of God's will towards us. What sensible person undertakes to be his own physician?"
Having a trusted spiritual advisor, whether that advisor is a priest or a holy lay person, is vital to the spiritual future of the convert.
Above all, remember patience is one of the most difficult virtues to master, but is the most essential to leading a Christian life.