CLAIM: Paul quotes Genesis 22:18 in his letter to the Galatians. He writes, “God gave the promises to Abraham and his child. And notice that the Scripture doesn’t say ‘to his children,’ as if it meant many descendants. Rather, it says ‘to his child’—and that, of course, means Christ” (Gal. 3:16 NLT). Paul takes notice of the fact that Genesis 22:18 refers to the singular child (or “seed”) of Abraham, rather than the plural children. However, critics notice that “seed” in the Hebrew was a collective singular noun. That is, even though it is singular, it refers to the entirety of Abraham’s offspring—not a singular person.
RESPONSE: In the original Hebrew language, the “seed” was indeed a collective singular noun, which referred to the nation as a whole. Indeed, Paul was well aware of the “collective sense of [seed],” because he appeals to it in Romans 4. Citing Genesis 15:5, Paul wrote, “[Abraham] believed, so that he might become a father of many nations according to that which had been spoken, ‘So shall your descendants [singular sperma] be’” (Rom. 4:18). This would result in “many nations” (Gen. 17:5). Paul, therefore, understood this concept of a “corporate seed.” However, there is another application of this prediction in play: A messianic prediction of Jesus. Paul’s messianic interpretation of a singular seed of Abraham is correct in Galatians 3:16.
First, in its original context, this prophecy was fulfilled in the single person of Isaac—not multiple offspring.
Second, a later psalmist claims that worldwide blessing will be given through a singular king. Psalm 72:17 states, “May the king’s name endure forever; may it continue as long as the sun shines. May all nations be blessed through him and bring him praise.” We see a similar interpretation in Psalm 89. There, the psalmist comments on 2 Samuel 7:12, and he continually uses the singular noun to refer to David’s descendants (Ps 89:4, 29, 36). Therefore, these later psalmists held the same interpretation as Paul. George writes, “Paul wanted to show that the greater fulfillment of the promise is not biological but Christological.”
Third, in its original context, Moses uses the future tense in Genesis 22:14 (“In the mount of the Lord it will be provided.”). This demonstrates that a future fulfillment was still in order, which wasn’t accomplished by Isaac.
Fourth, all of the similarities previously mentioned must have been on Paul’s mind, when he quoted verse 18. Therefore, the prophetic value of this passage is entirely warranted.
 See footnote. Ronald Y. K. Fung, The Epistle to the Galatians, The New International Commentary on the New Testament (Grand Rapids, MI: Wm. B. Eerdmans Publishing Co., 1988), 155.
 Timothy George, Galatians, vol. 30, The New American Commentary (Nashville: Broadman & Holman Publishers, 1994), 247.