As a dog
keleb (keh'-leb)
a dog; hence (by euphemism) a male prostitute -- dog.
returneth
shuwb (shoob)
to turn back (hence, away) transitively or intransitively, literally or figuratively
to his vomit
qe' (kay)
vomit -- vomit.
so a fool
kciyl (kes-eel')
fat, i.e. (figuratively) stupid or silly -- fool(-ish).
returneth
shanah (shaw-naw')
to fold, i.e. duplicate; by implication, to transmute (transitive or intransitive)
to his folly
'ivveleth (iv-veh'-leth)
silliness -- folly, foolishly(-ness).