Because ye were glad
samach (saw-makh')
probably to brighten up, i.e. (figuratively) be (causatively, make) blithe or gleesome
because ye rejoiced
`alaz (aw-laz')
to jump for joy, i.e. exult -- be joyful, rejoice, triumph.
O ye destroyers
shacah (shaw-saw')
to plunder -- destroyer, rob, spoil(-er).
of mine heritage
nachalah (nakh-al-aw')
something inherited, i.e. (abstractly) occupancy, or (concretely) an heirloom; generally an estate, patrimony or portion -- heritage, to inherit, inheritance, possession.
because ye are grown fat
puwsh (poosh)
to spread; figuratively, act proudly -- grow up, be grown fat, spread selves, be scattered.
as the heifer
`eglah (eg-law')
a (female) calf, especially one nearly grown (i.e. a heifer) -- calf, cow, heifer.
at grass
deshe' (deh'-sheh)
a sprout; by analogy, grass -- (tender) grass, green, (tender)herb.
duwsh (doosh)
to trample or thresh -- break, tear, thresh, tread out (down), at grass.
and bellow
tsahal (tsaw-hal')
to gleam, i.e. (figuratively) be cheerful; by transf. to sound clear (of various animal or human expressions)
as bulls
'abbiyr (ab-beer')
angel, bull, chiefest, mighty (one), stout(-hearted), strong (one), valiant.