The two Eckerlin manuscript books contain copies of letters and devotional writings written by Israel Eckerlin, who was the prior of the Brotherhood of Zion (the male celibate order) at Ephrata until 1745, when he and his two brothers, Samuel and Gabriel (also celibate male members) were expelled.

One of the letter books (the one with greatest damage to the cover) contains as its first document a letter in Israel Eckerlin’s own hand, dated in the body of the letter 1757. In the two books, it is the only document in Israel’s own hand. It is addressed to Mother Maria [Eicher], the prioress of the celibate women’s order, known by then as the Roses of Saron. The letter addressed to her, and another one addressed to the community, rehearse the many reasons that Eckerlin felt that Beissel was spiritually defective, and that he, Eckerlin, was the only qualified person to lead the community. There is a third letter book that is a companion to these two but not held by Elizabethtown College. These writings were completely unknown before 2012.

The Ephrata Chronicle (Chronicon Ephratense) states that after the Eckerlins left in autumn 1745, there was a book burning to destroy all of the materials that Israel had written (presumable all in manuscript). So the fact that copies of this many documents survive changes the picture of Eckerlin’s role and how he was remembered at Ephrata. The letter to Maria Eicher dated 1757, and another letter in one of the books also dated 1757 and addressed to the whole community were written from the Eckerlin brothers’ estate in what is now Preston County, West Virginia, along the Cheat River. It was extremely remote then, yet they had occasional visitors from Ephrata. Samuel also went regularly to Winchester, VA, to sell animal hides.