Sentence:  In truth it may be said he is a <WSD>"bundle of energy</WSD>", and when he enlists in any good cause, he is a living illustration of St. Paul's motto: "But this "one thing I do", forgetting those things which are behind and reaching forth unto those things which are before, I press toward the mark for the prize." 
Meaning of the word marked with <WSD> tags:  One who is especially lively, continually active, or industrious.