[10] In his posthumous work, Miscellanea Sacra, or Diverse Necessary Truths (1665) Jessey asserted that believing Christians "should have respect to all the Ten Commandments of the Law.

"[11] Jessey's biographer records that he kept the Sabbath in his own chamber, with only four or five more of the same mind after being convinced that the seventh day should be kept by Christians evangelically.

Five years later William Kiffin and others of Jacob's church at Southwark joined Spilsbury and divided equally in two parts under Praise-God Barebone and Henry Jessey.

In 1616 Henry Jacob organized at Southwark the oldest Independent church in England and served as pastor until 1622.

[15]In 1650, Jessey wrote The Glory of Iehudah and Israel in which he extolled the nobility of the Jews and proposed the reconciliation of Christianity and Judaism.

[17] He wrote an account[18] of the 1655 conference at Whitehall, at which Manasseh ben Israel put a case to the Parliamentary government of Oliver Cromwell, to lift the restrictions on Jews living in England.

[21] In lobbying for the rights of the Jews to official readmission to the country, and in high expectations from this, Jessey was an associate of John Dury and Nathaniel Holmes.

[22] In 1658 Jessey composed a work entitled An Information Concerning the Present State of the Jewish Nation in Europe and Judea.

[24] As well as raising money for the impoverished Jews of Palestine, Jessey was also well acquainted with two of the key figures disseminating information throughout Europe about the Jewish millenarian prophet Sabbatai Zevi.