Those who knew Jackson as a child in Greenville, S.C., remember him as a charmer–“that sweet little devil,” a neighbor lady reminisced–and a talker. “It sounded sometimes like there was actually some little man in there inside of him talking,” a teacher told Frady. “It was almost abnormal,” another said. “From his very start, he was already producing these… these oratorical wonders.” At Chicago Theological Seminary, he got a D in preaching because he wouldn’t write out sermons, but his impromptu orations made him a rising star in the civil-rights movement during the mid-’60s. On one occasion, Martin Luther King Jr. himself developed a sudden case of laryngitis when he had to follow the charismatic young Jackson to the podium. Jackson, born out of wedlock, attached himself to and modeled himself after King, but even when awestruck, he was never dumbstruck. One colleague remembered his assailing King with questions about theologians Paul Tillich and Reinhold Niebuhr and then rattling on with his own answers.

After King’s assassination, many of his circle, including his widow, thought that Jackson kept an indecently high profile. But Frady acquits him of cynicism (if not entirely of opportunism) and notes that Jackson’s regal presence and street credibility, as well as his now unrivaled oratory, made him King’s most plausible successor as the unofficial tribune of black Americans. For three decades now, he’s had the same amorphous job description. Frady sees him as a prophetic figure, miscast as a practical politician and “misplaced in time for his grand aspiration. Absent the great moral dramaturgy of King’s day, Jackson was left to struggle in the vague spiritual flats of a more prosaic and middling season to find his apotheosis, his mountaintop.” Jackson couldn’t have said it better–or more elaborately–himself. Today, at 55, he seems like a relic to a new generation. “The way he communicates, it’s a language that no longer connects,” says a former aide. “He might as well be the school principal.” This is a dispiriting note on which to leave Jackson’s mostly inspiriting story. But why do we think we haven’t heard the last of him?