Luke 10:20 - Ellicott's Commentary On The Whole Bible

Notwithstanding in this rejoice not. — Above all exercise of power was the consciousness of the divine life, the feeling that they had a Father in heaven who had, to speak after the manner of men, registered their names as citizens of His kingdom. That was the great blessing for them, and for all believing souls after them. The words leave open the question whether that registration conferred a title which they could not forfeit, and the current language of the Old Testament — the prayer of Moses, “Blot me out of Thy book” (Exodus 32:32), the warnings of Exodus 32:33; Deuteronomy 9:14; Deuteronomy 29:20 — would suggest the thought that even here the joy was to be tempered with fear and trembling. The reappearance of a like promise in Revelation 3:5 as the reward of obedience, and therefore conditioned by it, no less than the general tenor of the teaching of the Epistles (1 Corinthians 9:27; Galatians 2:21; 2 Peter 1:10), confirms this interpretation. It may be noted (1) that the better MSS. omit the word “rather,” and introduce the second clause abruptly — “Rejoice that your names are written...;” and (2), as implied above, that the root-thought of the image is that of a king taking the census of those who are citizens of his kingdom, as distinguished from aliens and foreigners. In Psalms 87:4-5, we have a memorable instance at once of the literal fact and of its spiritual application.