Obviously, Mormon is quoting the passage from Joshua. The children of Israel, like all people in a free society, were given the option to serve the Lord or serve Satan. Joshua's inspiring response was, as for me and my house, we will serve the Lord (Josh 24:15). Nephi expressed the same concept as follows, Wherefore, men are free according to the flesh; and all things are given them which are expedient unto man. And they are free to choose liberty and eternal life, through the great Mediator of all men, or to choose captivity and death, according to the captivity and power of the devil; for he seeketh that all men might be miserable like unto himself (2 Nephi 2:27).