Give to us clear vision that we may know where to stand and what to stand for — because unless we stand for something, we shall fall for anything.
Peter Marshall (1902-1949) Scottish-American preacher, author, US Senate chaplain
Prayer at opening of US Senate session (1947-04-18)
(Source)
This phrase has a significant history prior to Marshall's use of it; see Quote Origin: If You Don’t Stand for Something, You’ll Fall for Anything – Quote Investigator®.