A yolk is often placed around the necks of two or more beasts of burden (oxen, etc…) often, the tendency is for them to kick backwards in protest.

The farmer plowing with them will often use goads (sharp sticks) to control their kicking: the idea is that when these oxen kick backwards they feel a sharp prick.

Goad:

 –noun

1. a stick with a pointed or electrically charged end, for driving cattle, oxen, etc.; a prod.

2. anything that pricks or wounds like such a stick.

3. something that encourages, urges, or drives; a stimulus.

–verb (used with object)

4. to prick or drive with, or as if with, a goad; prod; incite.

—Synonyms – spur, push, impel.

Before God changed his name to Paul, the then Saul was on his way to the city of Damascus, Syria to persecute Christians when a bright light was all around him. He heard the voice of Jesus. The men around him could not hear the words that Jesus was saying to him.

“As he journeyed he came near Damascus, and suddenly a light shone around him from heaven. Then he fell to the ground, and heard a voice saying to him, “Saul, Saul, why are you persecuting Me?”…

And he said, “Who are You, Lord?” Then the Lord said, “I am Jesus, whom you are persecuting. It is hard for you to kick against the goads (pricks).” – Acts 9:3-5

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