Leaping
From Sensus Plenior
Leaping
Le 11:21 Yet these may ye eat of every flying creeping thing that goeth upon [all] four, which have legs above their feet, to leap withal upon the earth;
Allegorically, this critter is clean because although it flies and creeps on all fours, it is distinguished by 'prayer' and leaping into the air, or striving to live in the spirit, 'stripping off the flesh' and 'working out it's salvation with fear and trembling'. [1]
The word for leg is also that for kneel, as if in prayer. And leaping is also 'stripping off' or 'tremble'.