And as Esaias said before, Except the Lord of Sabaoth had left us a seed, we had been as Sodoma, and been made like unto Gomorrha. And as Esaias said before - What God designs to do with the Jews at present, because of their obstinacy and rebellion, is similar to what he has done before, to which the same prophet refers, Isaiah 1:9 : Except the Lord of hosts had left unto us a very small remnant, we should have been as Sodom, and we should have been like unto Gomorrha: i.e. had not God, who commands and overrules all the powers in heaven and earth, in mercy preserved a very small remnant, to keep up the name and being of the nation, it had been quite cut off and extinct, as Sodom and Gomorrha were. Thus we learn that it is no new thing with God to abandon the greatest part of the Jewish nation, when corrupt, and to confine his favor and blessing to a righteous, believing few.
Instead of remnant, שריד sarid, both the Septuagint and the apostle have σπερμα, a seed, intimating that there were left just enough of the righteous to be a seed for a future harvest of true believers. So the godly were not destroyed from the land; some remained, and the harvest was in the days of the apostles.