There are many versions online but I like this one the best.
I hope you like it as much as I do.
When he was a small boy, he had loved butterflies. Oh, not to net and
mount them, but to wonder at their designs and habits.
Now a grown man with his first son to be born in a few weeks, he found
himself once again fascinated with a cocoon. He had found it at the side
of the park path. Somehow the twig had been knocked from the tree and
the cocoon had survived undamaged and still woven to the branch.
As he had seen his mother do, he gently protected it by wrapping it in
his handkerchief and carried it home. The cocoon found a temporary home
in a wide-top mason jar with holes in the lid. The jar was placed on the
mantle for easy viewing and protection from their curious cat who would
delight in volleying the sticky silk between her paws.
The man watched. His wife's interest lasted only a moment, but he studied
the silky envelope. Almost imperceptibly at first, the cocoon moved. He
watched more closely and soon the cocoon was trembling with activity.
Nothing else happened. The cocoon remained tightly glued to the twig and
there was no sign of wings.
Finally the shaking became so intense, the man thought the butterfly would
die from the struggle. He removed the lid on the jar, took a sharp pen
knife from his desk drawer, and carefully made a tiny slit in the side
of the cocoon. Almost immediately, one wing appeared and then outstretched
the other. The butterfly was free!
It seemed to enjoy its freedom and walked along the edge of the mason jar
and along the edge of the mantle. But it didn't fly. At first the man
thought the wings needed time to dry, but time passed and still the
butterfly did not take off.
The man was worried and called up his neighbor who taught high school
science. He told the neighbor how he had found the cocoon, placed it in
the mason jar, and the terrible trembling as the butterfly struggled to
get out. When he described how he had carefully made a small slit in the
cocoon, the teacher stopped him. "Oh, that is the reason. You see, the
struggle is what gives the butterfly the strength to fly."
And so it is with us. Sometimes it's the struggles in life that strengthen
us the most.