# We should not be like Cain

"We should not do as Cain did"

# brother

This refers to Cain's younger brother Abel.

# Why did he kill him? Because

"He killed him because" 

# his works were evil and his brother's righteous

"Cain's works were evil and his brother's works were righteous" or "Cain did evil things and his brother did what was right"