Good'better'best

When young, in tones quite positive
I said, “The world shall see
That I can keep myself from sin;
A good man I will be.”

But when I loved Miss Kate St. Clair
'Twas thus my musing ran:
“I cannot be compared with her;
I'll be a better man.”

'Twas at the wedding of a friend
(He married Kate St. Clair)
That I became superlative,
For I was “best man” there.