Jesus might not yet have been baptizing in fire or even in the Spirit, but his signs showed that he was clearly the Spirit-endowed One who would baptize in the Spirit later (3:11, 16). As Jesus performed miracles, he alluded to a passage in the Old Testament, Isaiah 35:5-6, which mentioned some of the same signs he was performing. In so doing he reminded John's disciples that the works he was performing might be less dramatic than a fire baptism, but Isaiah had already offered them as signs of the messianic era (Goppelt 1964:77; Jeremias 1972:116; Borg 1987:165). Besides "seeing" Jesus perform the miracles of Isaiah 35, John's messengers could hear the good news Jesus preached to the poor (Mt 11:4-5), fulfilling Isaiah 61:1 (compare Lk 4:18). Jesus knew his mission, and John's doubts did not make him insecure; but he knew that John would recognize the words of Scripture.