'Nations' in the Bible

And I desire you to know, brethren, that I have many a time intended to come to you--though until now I have been disappointed--in order that among you also I might gather some fruit from my labours, as I have already done among the rest of the Gentile nations.

For the name of God is blasphemed among the Gentile nations because of you, as Holy Writ declares.

so that the promise should be made sure to all Abraham's true descendants; not merely to those who are righteous through the Law, but to those who are righteous through a faith like that of Abraham. Thus in the sight of God in whom he believed, who gives life to the dead and makes reference to things that do not exist, as though they did, Abraham is the forefather of all of us. As it is written, "I have appointed you to be the forefather of many nations."

Under utterly hopeless circumstances he hopefully believed, so that he might become the forefather of many nations, in agreement with the words "Equally numerous shall your posterity be."