The Greek word used in Galatians 4:29 is διώκω diōkō (Strong’s 1377) and means “pursue.” The Hebrew word used in Genesis 21:9 comes from צחק tsâchaq (Strong’s H6711), which means “to laugh (at).”
The same Hebrew word is found in other places in the Bible, such as in Genesis 18:12-15 where it is mentioned that Sarah tsachaq (laughed) when she heard she would give birth to a boy within a year. Another example is Genesis 26:8, where it says that Isaac tsachaq (was sporting) his wife.
That shows that Ishmael’s behavior toward Isaac was rather innocent and certainly not the image of persecuting. Why then does it say in Galatians 4 that Ishmael persecuted Isaac? What did Paul want to communicate to his readers?
When considering Paul’s arguments to the believers in Galatia, we can see that he used the son of the slave woman as an illustration for the Jews who relied on keeping the Law of Moses for their salvation and pressured the followers of Jesus Christ to do the same. He didn’t intend to qualify Ishmael’s behavior toward his younger brother. The best translation of dioko then, is “Ishmael pursued him.”
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