en_tn_condensed/mrk/11/28.md

They said to him

The word "They" refers to the chief priests, the scribes, and the elders.

By what authority do you do these things, and who gave you the authority to do them?

Possible meanings: 1) Both of these questions have the same meaning and are asked together to strongly question Jesus' authority and so can be combined. Alternate translation: "Who gave you authority to do these things?" 2) They are two separate questions, the first asking about the nature of the authority and the second about who gave it to him. (See: rc://en/ta/man/translate/figs-parallelism)

you do these things

The words "these things" refer to Jesus turning over the sellers' tables in the temple and speaking against what the chief priests and scribes taught. Alternate translation: "things like those you did here yesterday" (See: rc://en/ta/man/translate/figs-explicit)