# If a man is found kidnapping

"If you find a man kidnapping". This refers to using force to take a person away from his home and imprison him.
 
# any of his brothers from among the people of Israel

"any of his fellow Israelites"

# that thief must die

"then other Israelites should kill that thief as a punishment for what he did"

# you will remove the evil from among you

"you must remove from among the Israelites the person who does this evil thing" or "you must execute this evil person"