Alright, I will seek, to persuade you or at the very least demonstrate that ‘family’ is an acceptable gloss for ‘sperma’. For some reason some feel, the meanings ‘offspring’ and ‘children’ do not connote the idea of family. Without too much of a stretch we can begin to see that at the very least, children or offspring, is a subset of family. No, its not convertible, all family are not children or offspring, but all children or offspring (of a single descent) are family. Louw and Nida agree with this assessment, as, they include ‘sperma’ under the kinship category. Also, Liddell and Scott offer ‘race’ as a gloss. If you feel, family, is uncomfortable, then perhaps, race, is more fitting–He did not say races as if many but one race and that one is Christ; I will come back to Paul’s argument later and make brief observations. But we aren’t done yet. The LXX regularly translated ‘zera’ with ‘sperma’ and according to BDB ‘zera’ has the meaning ‘family or nation’ (282 4e). It had a special use of royal family (1 Kings 11:14). Certain exiles, were ‘unable to show their fathers house, their seed, whether they were of Israel,’ (Ezra 2:59) the idea of race or people is clear. Again, Moredecai, was ‘seeking the good of his people and speaking peace to all his race’ (Esther 10:3), people is parallel with race, implicitly showing the acceptablity of ‘race’, ‘people’ and ‘family’. Zera and sperma were mostly used in a collective sense, but there was also a since when a plurality of collective groups is brought in view. In later literature, Kiddushin 70b in the Babylonian Talmud, we read, ‘there are two families (zeryot) in Nehardea one called the house of Jonah and the other the house of ‘Urbathi…’
This I suggest is Paul’s meaning of sperma. I really hate to begin in Galatians 3:16 and then work from Galatians 2 forward, but I don’t really have the time to bear out Paul’s argument from 2:16-4:7. I suggested that Paul not being in a courtroom scene, but at a table, was establishing who had the right to eat at the table, who were children of God, and as Paul will establish later as the conclusion of his argument–or the question that implicitly drove his argument, who are the children of Abraham and heirs of the promises (Gal 3:29). The badge that would mark one out as ‘being delieved from the present evil age, for the age to come’ would not be determined by works of torah except through faithfulness of Jesus Christ–namely as Christ sums up God’s plan and his people in himself (2:19-21). Let me say upfront; those who are justified are saved, but that does not mean we need to reduce all terms: righteousness, grace, mercy, sanctification to mean salvation. Western individualism causes us to read God plan for the cosmos, I think, non-historically, and ultimately as, Going to heaven when you die (or what God is going to do for me and my soul)–as opposed to the Jewish way, deliverance from the present age (Gal 1:3) to be a blessing in the ha-olam ha-ba (the age to come).
Jesus’ death, was the mean through which Israel was delivered out of exile (yes, I know, you don’t see this in the text but I hope to be able to show that to you as well), so that the blessing of Abraham would come to the gentiles in Christ Jesus, so that we might receive the promise of the Spirit through faith (Galatians 3:10-14). Yet, God never intended for there to be two or more families. God did not promise that from Abraham many races, peoples, and families would bless the earth and inherit the blessings (Gen 12:7, 13:5, 17:8), but one family and that one family is summed up in Christ, as he argued in 2:19-21 and as he will argue in 3:26-29. I suggest too that this reading makes sense of Paul’s perplexing statement, ‘The law was ordered through angels by means of a mediator. Now a mediator is not for just one but God is one’. What? Moses was the mediator of the law, yet a mediator is not for just one (I take ‘one’ here to refer back to seed), that is, the Torah does not encourage only one family but actually builds a wall between the two (Jew and Gentile), but God is one, therefore, Paul seems to be concluded that he has only one family in mind (Galatians 3:20), which he argued elsewhere (Acts 17:24-26). The one God should only have one unified family (all this language about things being one has much to do with unity). You may not like this conclusions but it makes far more sense of the context than anything else I have read or heard.
Who are the true children of Israel? Not those who believe marking themselves out by the badges of Torah (Torah only reveals sin and builds a wall) but through the faithfulness of Jesus–who kept God’s covenant and redeem things on heaven and on earth. Not only are there no Jew and Gentile, but there also is not Roman or Barbarian distinctions, there is no family composed of women and another composed of men, Christ sums up all his people in himself (3:26-29). In fact, the very people who are seeking to declare themselves as belonging to Christ’s family by Torah are cutting themselves off from Him with the very thing they are clinging with nationalistic allegiance; they have fallen out of God favor (Gal 5:3-4). Note, again I am not saying salvation does not play a role here (nor that justification cannot mean declared in the right because of their salvation), but, I am saying Paul is dealing with who can eat at a table; who is in God’s family, and how many families does God desire.