{Under the altar} (hupokat(9320)tou thusiast(8872)iou). "Under"
(hupokat(935c)), for the blood of the sacrifices was poured at the
bottom of the altar ( Le 4:7 ). The altar of sacrifice ( Ex
39:39  40:29 ), not of incense. The imagery, as in Hebrews, is
from the tabernacle. For the word see  Mt 5:23f. , often in Rev.
( Re 8:3,5  9:13  11:1  14:18  16:7 ). This altar in heaven is
symbolic, of course, the antitype for the tabernacle altar ( Heb
8:5 ). The Lamb was slain ( 5:6,9,12 ) and these martyrs have
followed the example of their Lord. {The souls} (	as psuchas).
The lives, for the life is in the blood ( Le 17:11 ), were given
for Christ ( Php 2:17  2Ti 4:6 ). {Of the slain} (	(936e)
esphagmen(936e)). See  5:6 . Christians were slain during the
Neronian persecution and now again under Domitian. A long line of
martyrs has followed. {For the word of God} (dia ton logon tou
theou). As in  1:9 , the confession of loyalty to Christ as
opposed to emperor-worship. {And for the testimony which they
held} (kai dia t(886e) marturian h(886e) eichon). See also  1:9 .
Probably kai equals "even" here, explaining the preceding. The
imperfect tense eichon suits the repetition of the witness to
Christ and the consequent death.