John—if indeed John is the “other disciple” with Peter—was honest enough about his own experience of doubt to say that until the resurrection, he did not yet understand (20:9). This conflicts with the contrast that John presents to the Synoptic accounts, not least Mark, whereby revelation is much more blatant and conclusions are far more articulated early in the story. Here, though, in the simple confession of the same one who would suggest that witnesses to his glory should have got it, at least, we have a glimpse behind John’s theological agenda as a writer. The fact is, the resurrection remains the turning point for those closest to his glory. There is no way really to grasp what God is doing in the Messiah until we get to the empty tomb. Even then, it may be necessary to stick our fingers in the very scar tissue of his raised body.
Thomas actually represents much more than the modern reader, who must see with Lockean certainty or not perceive at all. Many of us subject to such a description sympathize with Thomas and assume that he must have shared our disposition, despite the whole setting being premodern. And he is indeed a symbol of the natural human tendency that found its home in the Enlightenment worldview, even if that tendency is not always lived out to the same extremity from culture to culture. But more than this, he is every reader, for John cannot transport the reader to see the risen Jesus or even the seven signs that preceded this final revelation. He is limited to testimony. Thus, blessed are those who have not not seen yet have come to believe (20:29). We might well paraphrase: blessed are those who have only read yet have come to believe (cf. 20:31). This is the astounding place that Scripture has taken in the Christian scheme of things. It is, somehow, the window on the revelation that brings us to confession. By it we may be blessed despite doubt, to believe and confess what only John would record in plain terms: My Lord and my God.