The word religion is a word of forced application when used with respect to the worship of God. The root of the word is the Latin verb ligo, to tie or bind. From ligo comes religo, to tie or bind over again, or make more fast--from religo comes substantive religio, which, with the addition of n makes the English substantive religion. The French use the word properly--when a woman enters a convent she is called a noviciat, that is, she is upon trial or probation. When she takes the oath, she called a religieuse, that is, she is tied or bound by that oath to the performance of it. We use the word in the same kind of sense when we say we will religiously perform the promise that we make.
But the word, without referring to its etymology, has, in the manner it is used, no definitive meaning, because it does not designate what religion a man is of. There is the religion of the Chinese, of the Tartars, of the Bramins, of the Persians, of the Jews, of the Turks, etc.