Why does Huck decide that there is something in religion afterall?

In Chapter Eight, the search party looking for Huck fills bread with mercury in the hopes that it would be attracted to his "dead" body. Huck is starving and prays for some food. Huck, of course, does not know the bread is sent to find his dead body. When he sees the bread he scoops one up. Huck figures that bread floating to him might be a sign that there might be something to religion after all.