You don’t have to know biblical Hebrew or Greek to know that translation is difficult and there is often not a one-to-one correspondence between a word in one language and a word in another. Usually, though, you don’t find such a discrepancy as one translation reading “yes,” and another reading “no,” but you do in Genesis 17:19.
The ESV:
Ge 17:18–19 — And Abraham said to God, “Oh that Ishmael might live before you!” God said, “No, but Sarah your wife shall bear you a son, and you shall call his name Isaac. I will establish my covenant with him as an everlasting covenant for his offspring after him.
The NIV:
Ge 17:18–19 — And Abraham said to God, “If only Ishmael might live under your blessing!” Then God said, “Yes, but your wife Sarah will bear you a son, and you will call him Isaac. I will establish my covenant with him as an everlasting covenant for his descendants after him.
The Hebrew has neither “yes” nor “no,” but begins God’s speech with “but.” In both the ESV and the NIV, the translators have added a word (yes/no) to make God’s response sound more natural in English. The KJV and Tanakh do without the yes/no, but most of the other translations begin with “no.”
Interesting. I’m actually preparing a lecture on English translations, so if you don’t mind, I’ll add your example to my list.
As a side note, there is no word in Biblical Hebrew for “yes.” So anytime you see this word in an English translation of the OT, you can know that its been inserted. (“ken”=”yes” is a later Talmudic development).