A.T. Robertson Commentary John 5:39

"Ye search the scriptures, because ye think that in them ye have eternal life; and these are they which bear witness of me;" — John 5:39 (ASV)

Ye search (εραυνατε). Proper spelling as the papyri show rather than ερευνατε, the old form (from ερευνα, search) as in 7:52. The form here can be either present active indicative second person plural or the present active imperative second person plural. Only the context can decide. Either makes sense here, but the reason given "because ye think" (οτ υμεις δοκειτε, clearly indicative), supports the indicative rather than the imperative. Besides, Jesus is arguing on the basis of their use of "the Scriptures" (τας γραφας). The plural with the article refers to the well-collection in the Old Testament (Matthew 21:42; Luke 24:27). Elsewhere in John the singular refers to a particular passage (2:22; 7:38; 10:35).

In them ye have eternal life (εν αυταις ζωην αιωνιον εχειν). Indirect assertion after δοκειτε without "ye" expressed either as nominative (υμεις) or accusative (υμας). Bernard holds that in John δοκεω always indicates a mistaken opinion (5:45; 11:13,31; 13:29; 16:20; 20:15). Certainly the rabbis did make a mechanical use of the letter of Scripture as a means of salvation.

These are they (εκεινα εισιν α). The true value of the Scriptures is in their witness to Christ (of me, περ εμου). Luke (24:27,45) gives this same claim of Jesus, and yet some critics fail to find the Messiah in the Old Testament. But Jesus did.