We Ought to Give the More Earnest Heed

The writer exhorts his audience to give heed to the things they have heard -- the "word spoken by angels" -- which have been confirmed by signs, wonders, miracles, and the gifts of the Holy Ghost, in view of the imminent judgment.  Since he's told us that angels are leitourgoi, ordinance priests, he imagines his readers in a temple context, preparing to meet the Lord at the veil.