Besought the LORD is literally “appeased the face of the LORD” (compare Exo 32.11). See the comments on this same Hebrew idiom in 1 Kgs 13.6. The somewhat archaic English verb besought is replaced by “entreated” in New Revised Standard Version. New Jerusalem Bible has “tried to placate Yahweh.” But some more common language renderings might be “pleaded with the LORD” (New Jewish Publication Society’s Tanakh), “begged the LORD” (New Century Version), or simply “prayed earnestly to….” Parola Del Signore: La Bibbia in Lingua Corrente makes explicit what Jehoahaz asked the LORD to do: “he begged the Lord to calm his anger.”
The LORD hearkened to him: The verb hearkened is also somewhat archaic. Both New International Version and New Century Version have “the LORD listened to him.” But in some languages the use of the verb “listened” alone might imply that there was no subsequent action. The context, however, demonstrates that God not only heard the prayer of Jehoahaz but that he also acted to answer it. Verses 22-25, however, seem to indicate that God did not deliver the Israelites from the domination of Syria until after the death of Jehoahaz.
The transition word translated for introduces the reason for Yahweh’s mercy. He answered the prayer of Jehoahaz because he saw how much the people of Israel were suffering and he felt sorry for them. It will sound more normal in certain languages to restructure along the lines of Good News Translation, presenting the reason before the result.
The two clauses he saw the oppression of Israel and how the king of Syria oppressed them may be rendered as a single clause in certain languages (so Good News Translation) since the second clause is a restatement and an amplification of the first one, focusing on the oppressor (the king of Syria) instead of the oppressed people (Israel).
Quoted with permission from Omanson, Roger L. and Ellington, John E. A Handbook on 1-2 Kings, Volume 2. (UBS Helps for Translators). New York: UBS, 2008. For this and other handbooks for translators see here .