1 Peter 1:8

A generous touch. The Apostle who has seen admires the love and joy of believers who have not seen the Lord; cp. John 20:29. Full of glory] in which God dwells: cp. Exodus 34:29; 1 Timothy 6:16. Faith leads into the presence of God, and adds to joy something which is unspeakable and divine: cp. Philippians 4:7.

The reference is to Isaiah 8:14. Whereunto also they were appointed] as the words of Isaiah show. God has indeed appointed the disobedient unto stumbling, but also His royal priesthood for their recovery.