Barnaby comes from the Aramaic Barnabas, translated as "son of encouragement," a name carried by a companion known in scripture for consistently backing others rather than seeking attention himself. It suggests support offered steadily, the kind that shows up in someone's corner rather than the spotlight.
The astrologer is able to control the actions of the stars if he knows the influx of their nature; is quite likely that he can modify the action before it happens. - Ptolomeus