The term harassed
comes from the Greek word eskulmenoi: literally meaning to be flayed
(to have one’s skin peeled off); “to be wounded (like sheep by thornbushes);
to be plundered (by robbers); or, more generally,
to be weary. The Greek for helpless (errimmenoiis) literally means thrown aside; to fall to the ground like a corpse (lying on the ground); and, in general "to be so weary that you can no longer walk.
The crowds were burdened to exhaustion by their religious leaders’ teachings.
The Greek word used in Matthew 9:36 and which in the ESV is translated as harassed,
eskulmenoi, actually means to be flayed
(that is, having one’s skin peeled off), “to be wounded (like sheep by thornbushes), or
to be plundered (by robbers), and, in a more general sense,
to be weary. The Greek word errimmenoiis, in the ESV translated as helpless, literally means thrown aside, to fall to the ground like a corpse (lying on the ground), and, in general "to be weary to such an extent that you can no longer walk.
This crowd’s weariness, conveyed by both these words, was a result of the heavy burden placed upon their shoulders by their religious leaders (see Matthew 11:28, Matthew 23:4).1
36 When he saw the crowds, he had compassion for them, because they were harassed and helpless, like sheep without a shepherd.