I heard him make a comment about it being grape juice during one of his TV presentations. Other than that one time, I honestly don't have a clue. I've never been to one his live seminars so I wouldn't know about those - wouldn't doubt it either. He is a stickler for detail as is readily apparent.
The Passover does require wine.
Grape juice didn’t exist in storage until about 100 years ago.
Grape juice is used when doing videos, due to the need for re-takes, to keep from becoming plastered.
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