Sonny Rollins at 78 is still a saxophone collosus, as he demonstrated leading his touring sextet Thursday night to open the Chicago Jazz Festival. His bent posture, shock of white hair and strong features give him the air of an Old Testament prophet, and his stamina may not be all it was when he was younger, but he brought wisdom, humor and intensity to an upbeat and swinging rendition of Irving Berlin’s “Falling In Love Is Wonderful,” sweet warmth  to Ellington’s “In A Sentimental Mood” (backed only by his rhythm section), and for a finale uproarious energy to a bare-bones Chicago blues. Read Neil Tesser’s article in the Chicago Reader for background on how Rollins cleaned up his act in Chicago, circa 1955, which accounts for his affection for the city to this day.Â