פירוש על ישעיהו 56:6

Also the sons of the stranger, etc. The eunuchs are mentioned before the sons of the strangers, because they are the last named (ver. 3). Comp. And I gave to Isaac, Jacob, and Esau, and I gave to Esau, etc. (Jos. 24:4).

To serve him. The service of the Lord consists in keeping His commandments.