Matthew 3:4
Now John dressed in clothing made of camel's hair and he wore a leather belt around his waist; he ate grasshoppers and wild honey [i.e., for his regular diet].
Matthew 11:8-9
What did you expect to see? A man dressed in fancy clothes? Look, people who wear fancy clothes live in kings' palaces.
Mark 1:6
John wore clothing made of camel's hair and he had a leather belt around his waist. He ate grasshoppers and wild honey.
Revelation 11:3
And I will give [authority] to my two witnesses and they will prophesy for 1,260 days, wearing sackcloth" [i.e., a black, coarse cloth made of goat's hair].