"For where your treasure is, there will your heart be also," Jesus told his hearers (Matthew 6:21). These words are deceptively profound. They speak to something that goes to the very core of scriptural Christianity, but something that also goes against our habits of mind.
It's easy to think of treasure as just having to do with material resources and the context seems to support this conclusion. In Matthew 6:24, Jesus says, "You cannot serve God and wealth," and off we go with ethical reflections about money. But money is not Jesus' primary concern. His first concern is the heart. If we don't get squared away on our understanding of the heart, we'll never figure out the money thing. So, as I often encourage, let's back up and go over this ground again.
Notice from other scriptures how characteristically Jesus draws attention back to the heart and away from the topic that started the conversation. To scribes and Pharisees from Jerusalem who had questioned his loyalty to Israel's traditions, he reminds them of Isaiah's prophecy: "This people honors me with their lips, but their hearts are far from me..." (Matthew 15:8). How is it that good religious people can be so far from God?
In another place, Jesus' detractors criticize him for not making his disciples keep all the traditions for washing before eating. The idea here is that if one does not wash a certain way, then one's hands are defiled. Whatever one's hands touch is therefore also defiled. Whatever is touched by something defiled is itself defiled, so the defiled food entering the body defiles the whole body. See where the attention has gone? Jesus tells his disciples in the post-argument teaching session (I'm summarizing), "It is not what goes into the mouth that defiles, but what comes out of the heart that defiles" (Mark 7:14-23). You can have clean hands and clean food, thereby meeting the conventional standard of "clean." But if your heart is defiled, everything else is defiled. This calls for wisdom.
Why does the Bible so often put the heart front and center? Because God created us to give ourselves to something, that is, to attach to something of value. One of the Bible's biggest jobs is to show us the beautiful and risky way God created human beings. The main biblical metaphor for this human characteristic is heart. Hundreds of times across scripture's pages we encounter this view of the heart. This is the central feature of human nature, which speaks directly to our predisposition to worship, to believe, to give and devote ourselves to something precious.
We moderns have not been taught to think of ourselves in such terms, even though modern psychology certainly recognizes the affective dimension and theorists of education have tried to incorporate their work into pedagogical techniques. In spite of these endeavors, we have been taught to assume that we are autonomous "information" gatherers who can manipulate morally neutral facts and figures to whatever ends we choose. In reality, nobody works this way. Stop and think of any activity that you deem important and you will see that you are not a mere calculating machine that spits out the right outcome on the basis of the inputs. We are made to give ourselves wholly to that which we value.
We can begin to see, therefore, why the divine injunction to love the Lord our God with all our hearts operates at the core of all human living. If we don't love the one true God who created us with a holy and glorious purpose, then we will love a less-than-God. Our hearts will give allegiance to something that cannot do what only God can do, which is the very definition of idolatry.
But also here we find a critical point that, again because of the dominant view of human nature, goes under-examined. We cannot love the way the Bible describes without engaging our understanding. We cannot love God apart from knowing God, and knowing God, though we confess our shortcomings and ignorance and our not comprehensively knowing God, must nevertheless engage our faculty for understanding. We must think. We need to spend more time thinking about thinking, to see how thinking is necessarily a heart-encompassing activity. It is precisely here that we Christians need to grow. We need to devote more time to thinking - to study and reflection, bathed in prayerful searching for the truth of God.
Not only does knowing God take this kind of effort, knowing our hearts does, too. It takes study. It takes wisdom and understanding. It takes moral courage. It takes time. It is what Jesus expects of his followers. It is what, by his Spirit, he graciously enables us to pursue.
Understanding the truth about our hearts is, indeed, a matter of life and death. Where goes your heart? What do you care about? Ultimately? Where goes your heart, there you find your treasure. And there you know your heart.