Bob Franke DOES feel very strongly that words to his songs should not be changed; I had a discussion with him about this very song and that very word, and he requested that I keep it unchanged.
When I introduced the song to my chorus last week, one of the members who is "physically challenged" said that she saw no reason to change the word!
It's true that younger folks might not grasp the meaning, so an explanation may be in order before you sing the song.

Wonderful song, isn't it? Best of luck as you sing it, Haruo!