# the commandment

Here this does not mean the Old Testament or the Ten Commandments but rather the instructions that Paul gives in 1 Timothy 1:3 and 1 Timothy 1:4.

# is love

Possible meanings are 1) "is to love God" or 2) "is to love people."

# from a pure heart

"from a mind that is honest" 

# good conscience

"a conscience that chooses right instead wrong"

# sincere faith

"genuine faith" or "a faith without hypocrisy"