I have argued for a long time that the History of the Rechabites (which is embedded in the Story of Zosimus) is a Christian composition. For specific, see my 2003 conference papers: "Is the Story of Zosimus Really a Jewish Composition?" and "The Rechabites in Patristic and Parabiblical Literature." Phil mentions Chris Knights, who also wrote on this work. He and I corresponded on the subject here and here, also in 2003. Several years ago Dr. Knights published an article revising his position in agreement with mine.
Another project on this text was noted here.
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