Ogha tarana Sutta
This discourse opens the Samyutta Nikaya with a paradox. The Commentary informs us that the Buddha teaches the devata in terms of the paradox in order to subdue her pride. To give this paradox some context, you might want to read other passages from the Canon that discuss right effort.
I have heard that on one occasion the Blessed One was staying near Savatthi in Jeta's Grove, Anathapindika's monastery. Then a certain devata, in the far extreme of the night, her extreme radiance lighting up the entirety of Jeta's Grove, went to the Blessed One. On arrival, having bowed down to him, she stood to one side. As she was standing there, she said to him, "Tell me, dear sir, how you crossed over the flood."
"I crossed over the flood without pushing forward, without staying in place."
"But how, dear sir, did you cross over the flood without pushing forward, without staying in place?"
"When I pushed forward, I was whirled about. When I stayed in place, I sank. And so I crossed over the flood without pushing forward, without staying in place."
[The devata:] At long last I see
a brahman, totally unbound,
who without pushing forward,
without staying in place,
has crossed over
of the world.
That is what the devata said. The Teacher approved. Realizing that "The Teacher has approved of me," she bowed down to him, circumambulated him — keeping him to her right; and then vanished right there.