Shoving Concrete

My friend said these words to me yesterday:
“How long do you think you can keep this up?”
I told him, “However is long enough.”
He laughed at me in a most loving way.

We sat, we talked for the rest of the day.
“At what point do you say it’s just too tough?”
I told him, “I will never give it up.”
Then he sighed and he explained it to me.

“I can see that you are shoving a wall,
A wall of concrete sure to hold ’til last,
If you get that, I suppose it’s okay.
But listen, my friend, I fear you may fall.
I do not want to witness your collapse,
‘Cause you did not know when to turn away.”