{Before me} (pro emou). Aleph with the Latin, Syriac, and
Sahidic versions omit these words (supported by A B D L W). But
with or without pro emou Jesus refers to the false Messiahs and
self-appointed leaders who made havoc of the flock. These are the
thieves and robbers, not the prophets and sincere teachers of
old. The reference is to verse  1 . There had been numerous such
impostors already (Josephus, _Ant_. XVIII. i. 6; _War_ II. viii.
I) and Jesus will predict many more ( Mt 24:23f. ). They keep on
coming, these wolves in sheep's clothing ( Mt 7:15 ) who grow
rich by fooling the credulous sheep. In this case "the sheep did
not hear them" (ouk (886b)ousan aut(936e) ta probata). First aorist
active indicative with genitive. Fortunate sheep who knew the
Shepherd's voice.