John Gill Bible Commentary

Thus saith the Lord, if heaven above can be measured,.... Either the space between the highest heavens and the earth; or the extent of the heavens, from one end of them to the other, which cannot be done by man; so the Targum, "as it is impossible that man should know the measure of the heavens above;'' otherwise it is measured by the Lord, for he hath "meted out heaven with a span", Isa 40:12; and the foundations of the earth searched out beneath: so as to be known what they are, or on what they are fastened, since the earth is hung upon nothing, Job 38:6; I will also cast off all the seed of Israel for all that they have done, saith the Lord; as the former cannot be, so neither the latter; when there was a very great rejection of the Jews for their disbelief of the Messiah, they were not all cast off; the Apostle Paul was an instance to the contrary, and so were others: "the remnant according to the election of grace"; and there is a time coming when all Israel shall be saved, Rom 11:5; nor shall any of the spiritual Israel be cast off by him, or cast away from him, so as to perish; the Israel, whom God foreknew, is chosen, redeemed, and whom he calls by his grace; no, not for all the sins and transgressions they have been guilty of, however they may deserve it. The reasons are, because of his unchangeable love to them; his unalterable covenant with them; the satisfaction his son has made for them; and the free and full pardon of their sins, which he has granted to them.