At the time he wrote this book in 1992, Dr. Michael Schiffman was "Spiritual Leader of Kehilat Yeshua Messianic Congregation in New York City. He served as an executive member of the Union of Messianic Jewish Congregations and is its theology chairman."
He wrote in the Introduction, "there exists a wide diversity among Messianic congregations today... In spite of their variations, these congregations are bound together through a common Messianic vision and heritage, and a common desire to preach the Gospel to the Jew first as well as the Gentiles. The purpose of this book is to examine the history and theology of Messianic congregations. This will bring a greater understanding of their role in the plan of God pertaining to Jewish people and Gentile believers." (Pg. 2-3)
Here are some additional quotations from the book (NOTE: page references refer to the 171-page 1992 edition):
"Although seventy-seven percent of spiritual leaders label themselves charismatic in orientation... only seventeen percent of them consider the exercise of spiritual gifts a major part of their services. Sixty percent consider it minor." (Pg. 123)
"Most Messianic congregations that participated in this survey have percentages of Jewish membership between twenty-five and fifty percent. This illustrates that Messianic congregations are not putting up a 'middle wall of partition' between Jewish and non-Jewish people. Both are equally members of these congregations."
"Jewish cultural elements in worship seem to have little value in outreach, but have value in identity and setting." (Pg. 150)