What did the Spirit of Christ testify through the Old Testament prophets?
The Spirit of Christ testified beforehand through the Old Testament prophets concerning the sufferings of Christ and the glory that should follow. They prophesied of the grace that should come, searching what manner of time the Spirit in them signified. This is what Peter writes in 1 Peter 1:10-11.
Les explains that the Old Testament prophets wrote by inspiration and searched diligently concerning the salvation and grace that was to come. The Spirit of Christ within them testified beforehand both the sufferings of Christ and the glory that would follow. Les suggests this glory refers to Christ's future Kingdom, when He will set it up, though the prophets could not fully understand it. Daniel was told to shut up the book, but at the end of time they would know.
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.