"Of which salvation the prophets have enquired and searched diligently, who prophesied of the grace that should come unto you: Searching what, or what manner of time the Spirit of Christ which was in them did signify, when it testified beforehand the sufferings of Christ, and the glory that should follow. Unto whom it was revealed, that not unto themselves, but unto us they did minister the things, which are now reported unto you by them that have preached the gospel unto you with the Holy Spirit sent down from heaven" (1 Pet.1:10-1).
Here Peter is saying that the prophets searched diligently in an effort to determine what the prophecies concerning Christ's suffering did signify but it was not revealed unto them. Even the Twelve Apostles, those closest to the Lord Jesus, did not realize that He was going to die (Lk.18:31-34) or be resurrected (Jn.20:9). They certainly did not know the "purpose" of the Cross, that "Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God" (1 Pet.3:18).
Roger M. Raymer writes: "Concerning this salvation (cf. 'salvation' in vv. 5, 9) the prophets...searched intently and with the greatest care their own Spirit-guided writings. They longed to participate in this salvation and coming period of grace and tried to discover the appointed time and circumstances to which the Spirit of Christ in them was pointing. The pondered how the glorious Messiah could be involved in suffering" (Walvoord & Zuck, The Bible Knowledge Commentary; New Testament [ChariotVictor Publishing, 1983], p.842).
Acts 2 dispensationalist Charles C. Ryrie writes that "It cannot be implied that the Israelite understood what the final sacrifice was. For if he had sufficent insight, to the extent of seeing and believing on the finished work of Christ, then he would not have had to offer the sacrifices annually, for he would have rested confidently in what he saw in the prefiguration. If the sacrifices had given a clear foreview of Christ, the offerer would have understood the truth of a completed atonement and would not have any consciousness of sins every year. But since the Scriptures say that he did have a consciousness of sins (Heb.10:2), he must not have seen very clearly 'the same promise, the same Saviour, the same condition, and the same salvation' as the believers see today" (Ryrie, Dispensationalism, [Moody Press, 1995], p.119).
Acts 2 dispensationalists John McArthur writes that "In Ephesians 3:3 Paul expresses a key thought relative to the church, 'By revelation he [God] made known to me the mystery.' That mystery 'in other ages was not made known unto the sons of men, as it is now revealed unto his holy apostles and prophets by the Spirit' (v. 5). Verse 6 identifies the mystery: 'That the Gentiles should be fellow heirs, and of the same body, and partakers of his promise in Christ by the gospel' " (McArthur, The Believer's Life in Christ; The Mystery of the Church).
This fairly represents the teaching of Acts 2 dispensationalim in regard to the meaning of "the mystery". However, this idea is clearly in error, and that is because the Christian is not told to make known this teaching to all the nations. It is the "gospel of grace" that is to be made known to all nations:
"The next day John seeth Jesus coming unto him, and saith, Behold the Lamb of God, which taketh away the sin of the world" (Jn.1:29).
Sir Robert Anderson writes that "This is not translation merely, it savours of exegesis. 'Who beareth the sin of the world' is what the Baptist said. His words were not a prophecy of what Christ would accomplish by His death, but a statement of what He was in His life. Mark the present tense, 'Who is bearing'. And while the word used in 1 Peter 1:2-24, and in kindred passages, is a sacrificial term, we have here an ordinary word for lifting and carrying burdens. When the Lord sighed in healing the deaf mute by the Sea of Galilee Mark 7:34, and when He groaned and wept at the grave of Lazarus, He took upon Himself, as it were, the infirmities and sorrows which He relieved, and made them His own" (Anderson, Types in Hebrews, [Kregel Publications, 1978], p.52).
Noted Bible expositor Alfred Edersheim writes: "That the view here given is that of the N.T...appears from a comparison of the application of the passage in St. Matt. viii. 17 with that in St. John i. 29 and 1 Pet. ii. 24. The words, as given by St. Matthew, are most truly a N.T. 'Targum' of the original. The LXX. renders, 'This man carries our sins and is pained for us;' Symmachus, 'Surely He took up our sins, and endured our labors;' the Targum Jon., 'Thus for our sins He will pray, and our iniquities will for His sake be forgiven.' (Comp. Driver and Neubauer, The Jewish Interpreters on Isaiah liii., vol. ii.) Lastly, it is with reference to this passage that the Messiah bears in the Talmud the designation, 'The Leprous One,' and 'the Sick One' (Sanh. 98 b]" (Edersheim, Life and Times of Jesus the Messiah [Wm. B. Eerdmans Publishing Co., 1971], Book 3, Chapter XIV, p.488).