There are four sorts of despair. There is the despair of devils;
there is the despair of souls in hell; there is the despair that is
grounded upon men's deficiency; and there is the despair that they
are perplexed with that are willing to be saved, but are too strongly
borne down with the burthen of their sins.

The despair of devils, the damned's despair, and that despair that a
man has of attaining of life because of his own deficiency, are all
unreasonable. Why should not devils and damned souls despair? yea,
why should not man despair of getting to heaven by his own abilities?
I therefore am concerned only with the fourth sort of despair, to
wit, with the despair of those that would be saved, but are too
strongly borne down with the burden of their sins.

I say, therefore, to thee that art thus, And why despair? Thy
despair, if it were reasonable, should flow from thee, because found
in the land that is beyond the grave, or because thou certainly
knowest that Christ will not, or cannot save thee.

But for the first, thou art yet in the land of the living; and for
the second, thou hast ground to believe the quite contrary; Christ is
able to save to the uttermost them that come to God by him; and if he
were not willing, he would not have commanded that mercy, in the
first place, should be offered to the biggest sinners. Besides, he
hath said, "And let him that is athirst come, and whosoever will, let
him take the water of life freely;" that is, with all my heart. What
ground now is here for despair? If thou sayst, The number and burden
of my sins; I answer, Nay; that is rather a ground for faith:
because such an one, above all others, is invited by Christ to come