Isn’t Ahmad ibn Hanbal ashamed of what he is doing?

Isn’t Ahmad ibn Hanbal ashamed of what he is doing?

Salih, the son of Ahmad ibn Hanbal, was met by Yahya ibn Mu’in who asked him:

“Isn’t your father ashamed of what he is doing?”

“What is he doing?” asked Salih.

“I saw him with al Shafi’i,” said Yahya. “Al Shaf’i was riding and he was on foot holding the rein of al Shafi’i's mount.”

Salih later related this to his father who said:

“If you see him again, tell him that I say that if he wishes to gain true knowledge and understanding, let him come and take hold of the other side of the reins of al Shafi’i's mount.”

[The Ethics of Disagreement by Taha Jabir al Alwani]