en_tn_condensed/mrk/10/05.md

"It was because ... this law," Jesus said to them.

In some languages speakers do not interrupt a quote to say who is speaking. Rather they say who is speaking at the beginning or end of the complete quote. Alternate translation: "Jesus said to them, 'It was because ... this law." (See: rc://en/ta/man/jit/writing-quotations)

because of your hard hearts that he wrote you this law

Long before this time, Moses wrote this law for the Jews and their descendants because they had hard hearts. The Jews of Jesus's time also had hard hearts, so Jesus included them by using the words "your" and "you." Alternate translation: "because your ancestors had hard hearts like yours that he wrote this law"

your hard hearts

Here "hearts" is a metonym for a person's inner being or mind. The phrase "hard hearts" is a metaphor for "stubbornness." Alternate translation: "your stubbornness" (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-metaphor)