Two simple sayings help me blast away at unbelief and, when my ship is sunk, have been bouys to keep me afloat.
These are daily on my mind and steady me. First, "put your feelings behind you and do the responsible thing." This is an effective weapon against man-pleasing and self-centeredness. The second is like it, "what is required is a long obedience in the same direction" (Eugene Peterson). This is particularly effective against spiritual laziness and reminds me to keep my vows.
Do any sayings serve as canons and bouys in your life?