A.T. Robertson Commentary Revelation 1:6

"and he made us [to be] a kingdom, [to be] priests unto his God and Father; to him [be] the glory and the dominion for ever and ever. Amen." — Revelation 1:6 (ASV)

And he made (κα εποιησεν). Change from the participle construction, which would be κα ποιησαντ (first aorist active of ποιεω) like λυσαντ just before, a Hebraism Charles calls it, but certainly an anacoluthon of which John is very fond, as in 1:18; 2:2,9,20; 3:9; 7:14; 14:2f.; 15:3.

Kingdom (βασιλειαν). So correctly Aleph A C, not βασιλεις (P cursives). Perhaps a reminiscence of Ex 19:6, a kingdom of priests. In 5:10 we have again "a kingdom and priests." The idea here is that Christians are the true spiritual Israel in God's promise to Abraham as explained by Paul in Ga 3; Romans 9.

To be priests (ιερεις). In apposition with βασιλειαν, but with κα (and) in 5:10. Each member of this true kingdom is a priest unto God, with direct access to him at all times.

Unto his God and Father (τω θεω κα πατρ αυτου). Dative case and αυτου (Christ) applies to both θεω and πατρ. Jesus spoke of the Father as his God (Matthew 27:46; John 20:17) and Paul uses like language (Ephesians 1:17), as does Peter (1 Peter 1:3).

To him (αυτω). Another doxology to Christ. "The adoration of Christ which vibrates in this doxology is one of the most impressive features of the book" (Moffatt). Like doxologies to Christ appear in 5:13; 7:10; 1 Peter 4:11; 2 Peter 3:18; 2 Timothy 4:18; Hebrews 13:21. These same words (η δοξα κα το κρατος) in 1 Peter 4:11, only η δοξα in 2 Peter 3:18; 2 Timothy 4:18, but with several others in Re 5:13; 7:10.