vv 27-28 You have heard the commandment that says, ‘You must not commit adultery.’ But I say, anyone who even looks at a woman with lust has already committed adultery with her in his heart.
This is just about the briefest of all the commandments. Cast your eye down the other 9 commandments and the sheer brevity of this one commandment is extraordinary – and it is so far reaching in its implications, much as ‘Thou shalt not steal’ is. Remember that parts of this sermon by Jesus deal with various aspects of the Ten Commandments, for example vv 21-22 look more deeply at the sixth Commandment – ‘Thou shalt not kill’. So here Jesus extends our understanding of the seventh commandment by saying ‘Looking and Lusting is every bit as much wrong as the doing.’
It is worth recalling the incident when Jesus met a wealthy young man who asked the question ‘“Teacher, what good deed must I do to have eternal life?”’ (Matthew 19:16) To this ‘Jesus replied: “‘You must not murder. You must not commit adultery. You must not steal. You must not testify falsely. Honour your father and mother. Love your neighbour as yourself]”
“I’ve obeyed all these commandments,” the young man replied.’
You then realise what a shallow view many people have of these commandments; they concern themselves entirely with the action the commandment forbids and never go beyond to consider the inner thoughts that defile a person’s thinking. That is where the sex battle is at its fiercest; there is a well-trodden path that leads from looking to lusting and if we find ourselves breaking through the barrier that Jesus sets we must pray for Holy Spirit power to block the pathway and live an inner life of purity.