In Revised Standard Version the last verse of this chapter is numbered 17, and it includes what appears as verse 18 in Good News Translation. But New Revised Standard Version has verse 18 also, in agreement with the UBS Greek New Testament.

The dragon was angry with the woman: the Greek verb “to be angry” appears in Revelation only here and in 11.18, where it is translated “raged”; see the related noun “anger,” “wrath” in 6.16, 17; 11.18.

Went off to make war: see the similar expression in Rev. 12.7.

The rest of her offspring: these “other descendants” are in addition to her son (verses 5, 13); they are the faithful Christians, as the next statement makes clear. In certain languages her offspring will be expressed as “her children and grandchildren” or “those who came down from her.”

Keep the commandments of God and bear testimony to Jesus: here the verb “to keep” means “to obey” (see 1.3). And for bear testimony to Jesus, the Greek has “and have (or, hold) the testimony of Jesus,” which may be translated as Good News Translation has it, “are faithful to the truth revealed by Jesus.” See the discussion of “testimony of Jesus Christ” in 1.2, where it is taken to mean “truth coming from Jesus Christ.”

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on The Revelation to John. (UBS Handbook Series). New York: UBS, 1993. For this and other handbooks for translators see here .