Progressives and liberals are well aware of the influence of the Christian right in American politics in recent decades.
But progressives and liberals may not be aware of the thesis advanced by Professor Borg about the historical Jesus -- to counter the so-called "literal" interpretation of the Bible advanced by certain Christians.
Borg emerged into national prominence as a member of the group of biblical scholars known as the Jesus Seminar. The task of the Jesus Seminar was to counter the propaganda advanced by Christians who insist on reading the Bible "literally," as they say.
The Jesus Seminar was co-founded by the biblical scholars Robert W. Funk, author of the accessible book HONEST TO JESUS: JESUS FOR A NEW MILLENNIUM (1996), and John Dominic Crossan, author of the pioneering scholarly book THE HISTORICAL JESUS: THE LIFE OF A MEDITERRANEAN JEWISH PEASANT (1991) and numerous other books, including a number of accessible books co-authored with Borg.
In numerous accessible books Borg presented his thoughts about the historical Jesus, including JESUS: A NEW VISION: SPIRIT, CULTURE, AND THE LIFE OF DISCIPLESHIP (1987), MEETING JESUS AGAIN FOR THE FIRST TIME: THE HISTORICAL JESUS AND THE HEART OF CONTEMPORARY FAITH (1994), THE GOD WE NEVER KNEW: BEYOND DOGMATIC RELIGION TO A MORE AUTHENTIC CONTEMPORARY FAITH (1997), JESUS: UNCOVERING THE LIFE, TEACHINGS, AND RELEVANCE OF A RELIGIOUS REVOLUTIONARY (2006), and CONVICTIONS: HOW I LEARNED WHAT MATTERS MOST (2014).
With Ray Riegert, Borg co-edited the book JESUS AND BUDDHA: THE PARALLEL SAYINGS (1997).
The accessible books that Borg co-authored with Crossan include THE LAST WEEK: THE DAY-BY-DAY ACCOUNT OF JESUS'S FINAL WEEK IN JERUSALEM (2006), THE FIRST CHRISTMAS: WHAT THE GOSPELS REALLY TEACH ABOUT JESUS'S BIRTH (2007) and THE FIRST PAUL: RECLAIMING THE RADICAL VISIONARY BEHIND THE CHURCH'S CONSERVATIVE ICON (2009).
In my estimate, Borg presents his basic thesis about Jesus most effectively in his last book, CONVICTIONS (2014).
Basically, Borg's thesis is that the historical Jesus had a profound mystical experience. Because the historical Jesus was a Jew, he naturally drew on his Jewish cultural conditioning to understand and express his experience. As a result, he set out in his public life to proclaim that the kingdom (or rule) of God has come upon him and can upon you, too. (The historical Jesus spoke Aramaic. But the canonical Christian scriptures are in Greek. The Greek is open to rendering the kingdom of God as the rule of God.)
As Borg notes in CONVICTIONS (pages 38-40), the famous Harvard professor William James discusses mystical experiences in his famous book THE VARIETIES OF RELIGIOUS EXPERIENCE. In an endnote Borg says, "The book is available in a number of editions. James treats mysticism in chapters 16 and 17. Though some of the book is dated, much of it continues to be of interest and importance. For those interested in the book as a whole, I suggest reading chapters 1, 6 through 17, and 20" (page 234).
But here is Borg's most important statement about mystical experiences in the book:
"Mystical experiences change the question of whether [the transcendent] God exists. To say the obvious, 'is-ness,' or 'what is,' is. What would it mean to argue about whether 'is-ness' is? The question of God's [transcendent] existence is no longer about whether there is another [transcendent] being in addition to the universe. Rather, the question becomes: What is 'is-ness'? What is 'what is'? What is reality? Is it simply the space-time world of matter and energy as disclosed by ordinary sense-perception and contemporary science? Or is it suffused by a 'more,' a radiant and glorious more [as mystical experiences often are]?" (page 45).
In the Christian tradition of thought out of which Borg comes, God has long been thought of as both transcendent and immanent. No doubt Christian mystics over the centuries have understood their profound mystical experiences as experiences of God's immanence.
However, for my present purposes, I am not interested in attributing profound mystical experiences to God, because I have no doubt that people who do not happen to believe in the monotheistic deity can have profound mystical experiences.
No doubt short-lived mystical experiences, such as Borg's own short-lived mystical experiences, can involve sensing the world as suffused in a radiant and glorious aura. However, I am not especially interested in discussing the radiant and glorious aura in short-lived mystical experiences.