Once when Zen master Seisetsu was seeing to the rebuilding of part of the monastery where he was teaching, a certain wealthy merchant came with a hundred ounces of gold, saying he wanted to donate it for the reconstruction project. Seisetsu took it without a word.
The next day the merchant came back to visit the Zen master. He remarked, “Although what I gave you was not so great an amount, it was an exceedingly costly donation for me. In spite of that, you didn’t say a word of thanks. Why is that?”
Seisetsu hollered, “I am planting your field of blessings; why should I thank you?”
The merchant was very embarrassed. He apologized and thanked the Zen master.