The block of granite which was an obstacle in the pathway of the weak, became a stepping-stone in the pathway of the strong.

The block of granite which was an obstacle in the path of the weak, becomes a steppingstone in the path of the strong.

A stepping-stone can be a stumbling block if we can't see it until after we have tripped over it.

The past is a stepping stone, not a millstone.

Permanence, perseverance and persistence in spite of all obstacles, discouragements, and impossibilities: It is this, that in all things distinguishes the strong soul from the weak.

Never be afraid to fail. Failure is only a stepping stone to improvement. Never be overconfident because that will block your improvement.