In your study guide to Paul’s Journey Letters, you ask a question about the passage in 2 Corinthians where Paul talks about “contemplating the Lord’s glory.” I wondered whether it was at all possible he was thinking (in part) of mystical practices. I’ve read that some Jews at the time were interested in having chariot visions, etc., and since “glory” is so closely associated with visions of God in the Old Testament, I wondered whether there could be a connection. Paul does talk elsewhere about seeing into layers of heaven.

This question is in session 14 on page 73 in the study guide to Paul’s Journey Letters: “What do you think it means to contemplate the Lord’s glory and be transformed by it? Have you begun to experience that? If so, talk about your experience.”
It’s true that some Jews, starting a couple of centuries after Paul, did try to have mystical visions of God’s heavenly enthronement, including visions of God being conveyed in a celestial chariot like the one Ezekiel saw that was formed by four living creatures or cherubim. Some interpreters have even suggested that Paul’s Damascus Road experience and his vision of the third heaven (described later in 2 Corinthians) are early examples of this type of mystical vision.
However, in light of the overall argument in 2 Corinthians, I think this is unlikely. As the study guide shows, that letter has four main parts. It culminates in a showdown, in the last part, between Paul and the so-called super-apostles. There he argues that the visions they pride themselves on are no real indication of spiritual maturity or authority—even though his own visions greatly surpass anything they’ve seen! Paul says he will not boast about visions like this, but only about his weaknesses, “so that Christ’s power may rest on me . . . for when I am weak, then I am strong.” Since Paul is building towards this climax, it would be inconsistent and self-contradictory for him to suggest earlier in the letter that he’s been seeking visionary experiences himself.
Rather, given his references to Moses and the tent of meeting, I think he’s picturing a similar, transforming, “face-to-face” relationship with God in his personal spiritual life and that he’s commending that kind of relationship to all of his readers. In the liberty of the Spirit, with nothing held back between us and God, “with unveiled faces” we “contemplate the Lord’s glory” and are “transformed into his image.”
Which brings me back to the end of the question in the study guide, about whether we’re experiencing this in our own lives. What things do we need to take out of the way between us and God so that we can directly contemplate his glory and be transformed?