# whoever breaks

"whoever disobeys" or "whoever ignores"

# the least one of these commandments and teaches

"any of these commandments, even the least important one, and teaches"

# whoever ... teaches others to do so will be called

"if anyone ... teaches others to do so, God will call that person"

# least in the kingdom of heaven

"the least important in the heavenly kingdom" or "the least important under the rule of our God in heaven"

# keeps them and teaches them

"obeys all these commandments and teaches others to do the same"