The state of assurance, exalted as it obviously is, is not an unchangeable state. Persons, who are in this state, are not only subject to strong temptations, but they sometimes fall into sin. And Satan will be likely to suggest to them under such circumstances, not only that the transgression of those, who have been so highly favored, is peculiarly aggravated, as it certainly is; but particularly that there no longer remains any hope for them, or but very little hope, in the divine mercy. We remark again, therefore, that no place should be given to such an unworthy suggestion as this. There is the same fountain of redemption opened for souls in the most advanced state of grace, when they fall into sin, as for the errors and sins of those, who have made the least progress. If, therefore, in any moment of imperfect inward recollection, or of sudden temptation, the soul is removed from its Center, and is led into any form of transgression, it should at once look to God with confidence, however deeply unworthy it may be; and repenting in the very moment of the perception of its wrong-doing, should believe, and be forgiven.
Persons, who are in the state of assurance of faith, possess, as a natural result of their assurance, all other Christian graces in a high degree; perhaps we may say, in the highest degree, especially love. Faith, if it exists in the degree in which it ought to exist, is the root, the fountain, from which all other Christian graces will certainly flow, both on their appropriate occasions and in their appropriate strength.
— edited from The Life of Faith (1852) Part 1, Chapter 16.