The phrase "high Sabbath" has been defined by Danny ben Gigi, former professor of Hebrew Language at Arizona State University, as synonymous with "Shabbat Hagadol", whichever Shabbat precedes Passover in any year. This viewpoint is based on the absence of references in Torah that refer to feast days as "high", although it is harder to reconcile strictly with New Testament chronology.
Read more about this topic: High Sabbaths