Let them be blotted out of the book of the living - That is, Let them cease to live; let them not be numbered among living people; let them be cut off. This language is taken from the custom of registering the names of persons in a list, roll, or catalogue, Exodus 32:32. See the notes at Philippians 4:3. Compare Revelation 3:5. The language has no reference to the future world; it is “not” a prayer that they should not be saved.
And not be written with the righteous - Let them not be registered or numbered with the righteous. As they “are” wicked, so let them be numbered; so regarded. Let them be reckoned and treated as they are. They deserve to be punished; so let them be. All that this “necessarily” means is, that they should not be treated as righteous, when they were in fact “not” righteous. It cannot be shown that the author of the psalm would not have desired that they should “become” righteous, and that they should “then” be regarded and treated as such. All that the language here implies is, a desire that they should be regarded and treated as they were; that is, as they deserved. The language is evidently derived from the idea so common in the Old Testament that length of days would be the reward of a righteous life (see Job 5:26; Proverbs 3:2; Proverbs 9:11; Proverbs 10:27), and that the wicked would be cut off in the midst of their days. See the notes at Psalms 55:23.