John Calvin Commentary 1 Peter 1:7

"that the proof of your faith, [being] more precious than gold that perisheth though it is proved by fire, may be found unto praise and glory and honor at the revelation of Jesus Christ:" — 1 Peter 1:7 (ASV)

Much more precious than of gold. The argument is from the lesser to the greater. For if gold, a corruptible metal, is considered so valuable that we test it by fire so that it may become truly precious, what wonder is it that God should require a similar trial for faith, since He considers faith so excellent? And though the words seem to have a different meaning, he still compares faith to gold and makes it more precious than gold, so that from this he might draw the conclusion that it ought to be fully tested. Furthermore, it is uncertain how far he extends the meaning of the words “tried” (δοκιμάζεσθαι) and “trial” (δοκίμιον).

Gold is, indeed, tested twice by fire: first, when it is separated from its dross; and then, when its purity is to be judged. Both modes of trial can very suitably be applied to faith. For when many dregs of unbelief remain in us, and when by various afflictions we are refined, as it were, in God’s furnace, the dross of our faith is removed, so that it becomes pure and clean before God; and, at the same time, a test of it is made, as to whether it is true or fictitious. I am inclined to accept these two views, and what immediately follows seems to favor this explanation. For just as silver has no honor or value before it is refined, so he intimates that our faith is not to be honored and crowned by God until it is duly tested.

At the appearing of Jesus Christ, or, when Jesus Christ shall be revealed. This is added so that the faithful might learn to hold on courageously until the last day. For our life is now hidden in Christ and will remain hidden, and, as it were, buried, until Christ shall appear from heaven. The whole course of our life leads to the destruction of the external man, and all the things we suffer are, as it were, the preludes of death. Therefore, it is necessary that we should cast our eyes on Christ, if we wish to behold glory and praise in our afflictions. For trials, to us, are full of reproach and shame, and they become glorious in Christ; but that glory in Christ is not yet plainly seen, for the day of consolation has not yet come.