Verses with the word plowman in the Old Testament (2 verses):

Isaiah 28:24
Doth the plowman plow all day to sow? doth he open and break the clods of his ground?

Amos 9:13
Behold, the days come, saith the LORD, that the plowman shall overtake the reaper, and the treader of grapes him that soweth seed; and the mountains shall drop sweet wine, and all the hills shall melt.