As far as the Old Testament age was concerned, the race of Israel was intended to have been a light to the Gentile nations, living as a holy nation faithful to Yahweh, whose Name and Law would become honoured amongst other nations:
“Look, as Yahweh my God commanded me (Moses), I have taught you laws and customs for you to observe in the country in which you are to take possession. Keep them and put them into practice and other peoples will admire your wisdom and prudence. Once they know what all these laws are, they will exclaim “No other people is as wise and prudent as this great nation (Israel)” (Deut4:5,6).
Some readers will be aghast at Moses’ statement: the Law (Torah) actually to be PRACTICED so that the world would come to admire Israel AND HER LAW. Yes indeed, that was the intention. The witness of Israel being faithful to the Law provided through Moses was meant to have been the rest of the world’s “preparation for the Gospel” i.e. their future submission to the Lordship of King Jesus when He eventually came to do exactly what John Baptist expected Him to do: destroy the enemies and oppressors of God’s people and judge the whole world, i.e. put it to rights. Then, supported by the Jewish Nation (the sons of the Kingdom – Mt8:12), He would establish God’s Kingdom on Earth, reconciling other nations to God and each other by inculcating a way of peace along the lines of Isaiah2:4. It didn’t pan out that way and St Paul explains why (if only he were understood). It’s not the Old Testament being hyper-allegorical, it’s the fellowship of the secret! (cf. Eph3:8-11).