And they that dwell upon the earth shall rejoice over them, and make merry, and shall send gifts one to another; because these two prophets tormented them that dwelt on the earth; rejoice and make merry, that dwell (present, though future in meaning; the present tense rendering the description more graphic).
Those dwelling on the earth are the ungodly, the worldly. "They send gifts," in accordance with Oriental custom on joyful occasions (cf. Revelation 11:9). "The prophets, the witnesses, tormented;" probably rather by the delivery of their message, which would affect the conscience of men, than by the plagues referred to in Revelation 11:6, though both may be meant.
Alford, Bengel, and Dusterdieck favour the latter view of the two; Hengstenberg takes the former.