I fall into all kinds of temptations. Most of them are pretty obvious and lack creativity. Lust. Envy. Sloth. Pride. The typical seven deadly sin stuff. It’s all pretty dull and garden variety. We all do them and we know it.
But the devil’s best tool as a tempter is far more wily than simply offering us these obvious temptations. He does offer them, but his subtly slips something far more deadly into our imaginations while we expend energy warding off the obvious temptations.
Medieval theologians concluded that abstraction is the devil’s most effective tool. Abstraction is the first step toward most of our sins.
Abstraction is essential to lust. Sex ceases to be about making love and more about getting off. Abstracted, sex ceases to be about a relationship and all about a feeling of euphoria. 
Not only porn, but our culture’s emphasis on technique, are results of this abstraction as Marva Dawn points out in her book Sexual Character: Beyond Technique to Intimacy.
Abstraction is behind all theft. The person being stolen from becomes intangible and the goal of taking what they have becomes the real thing.
Abstraction takes the taste out of food. All of our focus on calories and nutrients has done nothing for our experience of the flavors of food. Instead, we’ve ended up with processed food-like substances that are more like cardboard than the richness of the earth. Similarly, abstraction reduces beer and wine to alcohol to get drunk. Good drinking is about the savoring of life, not the dulling of it.
Abstraction is the fuel for every grudge. When I hold a grudge against someone, I reduce that person to how I feel about a few things he or she did that caused me to feel that way. All of the color and dimension of that person’s life drains away and I’m left with only those few actions and me feelings about them. The first step toward reconciliation is always a return to a more full-bodied view of the person I’d been upset with.
Abstraction is what kills ecosystems. When a living forest is no longer seen for what it is and is reduced to dollar amounts on a spreadsheet with tabs for lumber, paper, and housing development, the environment ends up getting ripped apart.
Abstraction creates financial crises. When loyal workers are reduced to “headcount” and become “human capital” to be kept or spent or lost without any relational blowback, it becomes less painful for personnel officers to cut them. But there shouldn’t be any reduction in pain. These are real people who will no longer have jobs.
Abstraction is what enables genocide and most warring. The Nazis were masters of abstraction, shaving Jewish heads to remove the distinctiveness of hair and tattooing numbers to erase identities. Rwanda. Sudan. Serbia. Indians on the American frontier. In each of these cases and more, whole groups of people were reduced to ideas, to racial slurs and then killed. Reducing any group of people to a label is an essential step in justifying their deaths.
Abstraction leads to slavery. It leads to actual slavery as slaves are treated as less that human and it leads to the slavery of credit debt and usury as getting money becomes the primary goal of lenders, not helping people finance their lives.
And on we could go.
Reducing people and things to ideas or numbers makes them easy to categorize and dismiss and use or misuse. So, we should always tread carefully when walking into the abstract realm of numbers and concepts. There are times when they can be helpful, but they are always dangerous.
The Bible has an interesting relationship with numbers. On one hand, there’s actually a book of Numbers. (I once tried to get a church finance committee to do its devotions out of Numbers, but they resisted, preferring to avoid dealing with the Bible and sticking to their spreadsheets.) And there are plenty of times when we get lists of numbered people which are sanctioned by God. But then there is God’s massive reaction against David counting the people. Numbers are dangerous.
Much good can be done when we run the numbers and make responsible decisions for our lives and for the lives of our community by doing so. Counting people can help us meet their needs. Counting votes can tell us the will of the people.
Numbers are powerful tools and should be used as such; with the same respect I have for the whirring blade of my table saw.
Abstraction has its place, but it needs to be a limited place. What we need more of is real, concrete interactions.
But even our use of language has become abstract. Words that used to be anchored in the physical world are now lost to the ethereal world of ideas.
The word “right” has been reduced to the concept of being correct and not wrong. But it initially had to do with stranding up straight — at a right angle from the ground. The opposite was crooked, bent. An upright person was not a crook.
We’ve replaced real-world images with intangible concepts. Is it any wonder kids are more interested in playing video games instead of going outside?
In his brilliant little book The Great Divorce, C.S. Lewis doesn’t write about divorce. He writes about the differences between heaven and hell. 
In the book, heaven in the realm of ultimate reality where everyone is moving closer and closer together and everything is getting more and more solid. On the other hand, hell is the realm of phantoms, where everyone is getting further and further away from each other and there is no substance to anything at all — you can have any house you imagine, but it won’t keep the rain off of you.
God the Creator has made and offers us the really Real. The devil offers us enticing promises that disappear with a puff of wind.
Always choose the real over the abstract.