'Therefore observe that contrition in a new-born soul ordinarily is in proportion to his former vanity. To whom much is forgiven, they love much: and this is a fountain of evangelical repentance. As a traitor condemned to die, receiving a pardon, would wonderfully break his heart to think he should be so villainous to so gracious a prince: so it is with a Christian that beholds God's mercy to him.
Christians after their conversion desire to see their sins to the utmost, with all the circumstances that make them hateful, such as the object, nature, person, time, age, etc. in which, or how they were done, that so they may be more humbled for them.
If it be not so (it may be otherwise, for God is a free agent, and is not tied to any proportion of sorrow) then such troubles as these usually seize on them:
First. They are often afflicted with this, that their conversion is not thorough and sound, and so do not perform the duties of godliness with such heartiness and cheerfulness.
Second. They are many times haunted with listlessness and coldness in their progress in Christianity.
Third. They are visited with some cross or other that sticks by them: to make them lay a greater load upon sin.
Fourth. They are more subject to be overtaken with their easily besetting sin, because they have no more sorrowed for it; for the less it is sorrowed over, the more it ensnares men.
Fifth. Some of them have been assaulted upon their bed of death with sorrowful and strong temptations. Not that men should think this is always the reason of it, for God has aims in all His works known only to Himself; but I have known some have so been troubled, and this may be in great mercy to make a weak conversion more strong. Lest any Christian should be troubled at it, note in contrition there must be sorrow of heart because of sin: there must be a dislike of it in the will: there must be a strong reasoning in the mind out of the word of God against sin; this is the sinew of repentance: there must be a resolution, and striving and watching against it, like Job who made a covenant with his eyes, Job 31: l: there must be a grieving that he is not excelling in all these, and here he must make up what he wants in the former. These be in some measure in all Christians. Some are more eminent in one part, some in another; as Joseph had little sorrow, but a strong resolution, because he had so strong a temptation, and withstood it; he had strong reasons beyond nature to resist sin, and resolve against it: so that it is not so much the measure as the truth of every part that is required. But if they be not excelling in great sinners, they are to mourn for the want of them. To help here, observe these ten degrees of repentance, or rather helps to humiliation.'
The ten helps can be read at http://www.bibleteacher.org/bolton.htm