For those doubting their regeneration -- Case 3.

Case 3. "I find the motions of sin in my heart more violent since the Lord began his work on my soul, than they were before that time. Can this consist with a change of my nature?"

Answer. Dreadful is the case of many, who, after God has had a remarkable dealing with their souls, tending to their reformation, have thrown off all bonds, and have become grossly and openly immoral and profane; as if the devil had returned into their hearts with seven spirits worse than himself. All I shall say to such people is, that their state is exceedingly dangerous; they are in danger of sinning against the Holy Spirit: therefore, let them repent, before it be too late.

But if it be not thus with you; though corruption is stirring itself more violently than formerly, as if all the forces of hell were raised, to hold fast, or bring back, a fugitive; yet these stirrings may consist with a change of your nature. When the restraint of grace is newly laid upon corruption, it is no wonder if it acts more vigorously than before, "warring against the law of the mind," Rom. 7:23. The motions of sin may really be most violent, when the new principle is brought in to cast it out. The sun sending its beams through the window, discovers the motes in the house, and their motions, which were not seen before; so the light of grace may discover the risings and actings of corruption, in another manner than ever the man saw them before, though they really do not rise nor act more vigorously.

Sin is not quite dead in the regenerate soul; it is but dying, and dying a lingering death, being crucified: no wonder there are great fightings, when it is sick at the heart, and death is at the door. Besides, temptations may be more in number, and stronger, while Satan is striving to bring you back, who are escaped, than while he only endeavored to retain you: "After you were illuminated, you endured a great fight of affliction," says the apostle to the Hebrews, chap. 10:32. But "cast not away your confidence," ver. 35. Remember his "grace is sufficient for you," and "the God of peace shall bruise Satan under your feet shortly."

Pharaoh and his Egyptians never made such a formidable appearance against the Israelites, as at the Red Sea, after they were brought out of Egypt: but then were the pursuers nearest to a total overthrow, Exod., chap. 14. Let not this case, therefore, make you raze the foundations of your trust; but be you emptied of self, and strong in the Lord, and in the power of his might, and you shall come off victorious.

--Thomas Boston, from Human Nature in Its Fourfold State.