9:6 upper chambers. This can be rendered “palace” or “temple” (cf. Rev. 11:19). The Hebrew word means “steps” or “stairs,” such as those used to enter the temple, particularly the temple of the end time (Ezek. 40:6, 22, 26, 31, 34).

vault. Here it perhaps means the arch or vault of heaven (Ex. 24:10 note).

the Lord is his name. An exact repetition of the phrase in 5:8.