When Zen Master Chengzhuo preached the Dharma in Yuan-jue Temple, the Dharma Yuán (relationships) was very prosperous. Every time he lectured, people were so crowded that there was no way to pass through. Therefore, some believers suggested building a more spacious lecture hall.
A believer packed fifty taels of gold in a bag and sent it to the temple to Zen Master Chengzhuo, explaining that he wanted to donate it to build a lecture hall. After the Zen master accepted it, he was busy doing other things. The believers were very dissatisfied with this attitude, because fifty taels of gold is not a small amount, and can help ordinary people live for several years. But when the Zen master received this huge sum of money, he didn't even say "thank you", so he followed Chengzhuo and reminded him: "Master! There are fifty taels of gold in my bag."
Zen Master Chengzhuo responded casually: "You have already said it, and I know it too." The Zen Master did not stop, and the disciple raised his voice and said: "Hey! Master! The fifty taels of gold I donated today is not a small amount! Don't you even want to say the word 'thank you'?"
The Zen master happened to stop in front of the Buddha statue in the Main Hall: "Why are you nagging like this? You donated money to the Buddha, why do you want me to thank you?"
When you Dāna, you are doing your own merit. If you want to treat merit as a kind of business, I will say "thank you" to you on behalf of Buddha. Please carry "thank you" back. From now on, you and the Buddha are "the goods are delivered and the bill is cleared".