Charles Ellicott Commentary 1 Peter 4:13

"but insomuch as ye are partakers of Christ`s sufferings, rejoice; that at the revelation of his glory also ye may rejoice with exceeding joy." — 1 Peter 4:13 (ASV)

But rejoice.—This is the opposite of being bewildered by it, for “rejoicing” in it implies a recognition of its character and purpose. The word rendered “inasmuch as” (which also occurs in 2 Corinthians 8:12) seems to mean “in proportion as”: “the more nearly you are made to share Christ’s sufferings, the more you should rejoice.” In the Acts of St. Probus (a Cappadocian), when, after many other tortures, the judge ordered them to heat some nails and run them through his hands, the martyr exclaims, “Glory to You, Lord Jesus Christ, who have even deigned to let my hands be pierced for Your name’s sake!”

Christ’s sufferings.—Rather, the sufferings of the Christ. (Compare to the note on 1 Peter 1:11.)

That—i.e., “in order that.” This is to be attached to “think it not strange, but rejoice”—“in order that at the revelation of His glory also (as now, in the sharing of His sufferings) you may rejoice (the word is the same), exulting.” Such a recognition of the meaning of suffering, such a rejoicing in suffering now, is a sure means to rejoicing in glory also hereafter.