Of knights and snails

One the funnest parts of looking at medieval art is running across an illustration of a knight fighting a snail. 

There are many theories as to what these snails are doing in the art, but not a one of them matches my own, which I came up with this year while reading through the Psalms with my family. Take a look at this:

Psalm 58

1 Do ye indeed speak righteousness, O congregation? do ye judge uprightly, O ye sons of men?
2 Yea, in heart ye work wickedness; ye weigh the violence of your hands in the earth.
3 The wicked are estranged from the womb: they go astray as soon as they be born, speaking lies.
4 Their poison is like the poison of a serpent: they are like the deaf adder that stoppeth her ear;
5 Which will not hearken to the voice of charmers, charming never so wisely.
6 Break their teeth, O God, in their mouth: break out the great teeth of the young lions, O Lord.
7 Let them melt away as waters which run continually: when he bendeth his bow to shoot his arrows, let them be as cut in pieces.
8 As a snail which melteth, let every one of them pass away: like the untimely birth of a woman, that they may not see the sun.
9 Before your pots can feel the thorns, he shall take them away as with a whirlwind, both living, and in his wrath.
10 The righteous shall rejoice when he seeth the vengeance: he shall wash his feet in the blood of the wicked.
11 So that a man shall say, Verily there is a reward for the righteous: verily he is a God that judgeth in the earth.

 

The psalmist is describing how ferocious and dangerous the enemies of God appear, but then in verse 8 he says, "As a snail which melteth, let every one of them pass away."

In other words, they appear unconquerable, but they really aren't. 

The popular idea about this image is that the knight has given up and is begging mercy of the victorious snail, but I believe he has recognized that this is spiritual warfare, so he has laid down his sword and is praying to God for deliverance.

What's your favorite theory?