“You have heard that it was said, ‘You shall not commit adultery.’ But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.”‬‬ (CSB – Read the chapter) 

Jesus said some uncomfortable things during His ministry. This particular saying is close to the top of the pile. Frankly, it’s even worse than what He says next about cutting off the hand or gouging out the eye that causes us to sin because those are obvious instances of hyperbole. This one isn’t. This one is just hard. There’s no wiggle room here. So…what do we do with it. 

Well, we start by owning it. If you are committed to one person and you have let your heart and mind dwell intimately on another, you have been unfaithful to your one. It’s really that simple. What Jesus says here isn’t difficult to understand at all. And, if you’ve done that, you need to repent of it (which necessarily means not doing it anymore) and work toward rebuilding trust where it has been broken. 

That’s the small picture. There is, however, a bigger picture that is just as important. Jesus’ bigger point here and in much of the rest of this part of the Sermon on the Mount is that sin starts in the heart. 

Much of the thinking about sin in Jesus’ day was concerned solely with the external. The Law defined what was and wasn’t sin and the Law was very physical. It was concerned with things we should and should not do. As long as you were sticking with the former at the expense of the latter, you were okay. What happened on the inside didn’t matter. 

Jesus said, “Not so fast.” He made the point in many different ways, some direct, some more indirect, that what happened on the outside was controlled by what was happening on the inside. What happened on the inside is what mattered most. If you’ve got something sinful happening on the inside, eventually it is going to work itself out on the outside. 

Here’s what all of that means: Pay attention to your heart. Pay attention to what you allow access to your mind. Junk there is hard to root out and it will poison your processes of thinking and reasoning until it’s gone. If you’ve got ungodly stuff going on in your heart, that’s a sign that something is wrong and needs addressing. Specifically, something is wrong in your relationship with God. It’s a sign you aren’t dwelling with Him as fully as you could. It’s a sign that it’s time to get to work. 

So…get to work. Find someone with whom you can safely talk about what’s going on inside and have them work through the thoughts and emotions with you. If there is something for which you need to repent, do so. If there are bad habits you need to break, get the help you need and do that. If there are good habits you need to put in place, do that (and by the way, I believe it takes 21 days of doing something to make it a habit). Get the inside fixed so you can make sure the outside isn’t just a coat of whitewash on a smelly tomb.