According to Edwards, what do healthy, strong members of the congregation foolishly believe? Why do they think this?

As
Edwards make abundantly clear, believers, no matter how strong they may be, can be cast down
into the fiery pit of hell just as quickly as anyone else. The same goes for those who are
healthy. An individual's health, no more than his or her care, prudence, or righteousness, is
enough to keep them out of hell. If God is angry with you, then you're going to hell, and
there's nothing you can do about it.

What Edwards is challenging here is the
notion that there's something believers can do to prevent themselves from being cast down into
hell for all eternity. Evidently, some backsliders among Edwards's congregation have got in into
their heads that their strength and good health are clear signs that they are part of the elect,
predestined to go to heaven.

Edwards wants to disabuse anyone of such a
belief. He takes great pains to emphasize that the decision to send sinners to hell is God's and
God's alone and that therefore no one has the right to be so complacent as think that
they're...