PLOW
At first they were made of wood, cork oak being the most suitable for this. The poor peasants could not at first have a plow with iron reinforcement.
However, by the time of David a more general use of iron in relation to agriculture is already mentioned (2 Sam. 12:31). The action of plowing is used metaphorically of intense affliction (Ps. 129:3).
There is no doubt that this is a prophetic mention of the treatment that the Lord Jesus suffered on earth, especially his scourging.