John Calvin Commentary 1 Peter 1:10

"Concerning which salvation the prophets sought and searched diligently, who prophesied of the grace that [should come] unto you:" — 1 Peter 1:10 (ASV)

He therefore commends the value of salvation, because the prophets had their minds intensely focused on it; for it must have been a matter of great importance and unique excellence that could have ignited such a spirit of inquiry about it in the prophets. But God’s goodness toward us shines forth even more clearly in this, because much more is now revealed to us than what all the prophets attained through their long and anxious inquiries. At the same time, he confirms the certainty of salvation by this very antiquity, for from the beginning of the world, it had received clear testimony from the Holy Spirit.

These two things should be distinctly noted: he declares that more has been given to us than to the ancient fathers, to magnify the grace of the gospel by this comparison; and then, that what is preached to us concerning salvation cannot be suspected of being new, for the Spirit had previously testified about it through the prophets. Therefore, when he says that the prophets searched and diligently inquired, this does not pertain to their writings or doctrine, but to the private desire with which each one was fervent. What is said later refers to their public office.

But so that each point may be clearer, the passage should be organized into certain propositions.

1. The Prophets, who foretold the grace that Christ revealed at His coming, diligently inquired about the time when full revelation was to be made.
2. The Spirit of Christ predicted through them the future condition of Christ’s kingdom, as it is now, and as it is still expected to be—namely, that Christ and His whole body are destined to enter into glory through various sufferings.
3. The prophets ministered to us more abundantly than to their own age, and this was revealed to them from above; for only in Christ is the full display of those things of which God then presented merely an obscure image.
4. The Gospel contains a clear confirmation of prophetic doctrine, and also a much fuller and plainer explanation; for the salvation which He formerly proclaimed, as it were, at a distance through the prophets, He now reveals openly to us, as it were, before our very eyes.
5. It is therefore evident how wonderful is the glory of that salvation promised to us in the Gospel, because even angels, though they enjoy God’s presence in heaven, still burn with the desire to see it.

Now all these things tend to show this one thing: that Christians, elevated to the height of their felicity, should overcome all the obstacles of the world. For what is there that this incomparable benefit does not reduce to nothing?

Of which salvation. Did the fathers not have the same salvation as we have? Why then does he say that the fathers inquired, as though they did not possess what is now offered to us? The answer to this is plain: salvation here is to be understood as that clear manifestation of it which we have through the coming of Christ. Peter's words mean nothing other than what Christ said, when He stated:

“Many kings and prophets have desired to see the things which ye see, and have not seen them” (Matthew 13:17).

Since, then, the prophets had only a limited knowledge of the grace brought by Christ, they justly desired something more regarding its revelation. When Simeon, after seeing Christ, calmly and with a satisfied mind prepared himself for death, he showed that he was previously unsatisfied and anxious. Such was the feeling of all the godly.