I am engaged in a personal study of the contemplative life and the related doctrine of Christian perfection. In both cases, Christianity is viewed as a “matter of the heart.”
At the same time, I’ve run across those who believe we’re copping-out when we speak too much of the heart. It’s not “real,” they say, until it’s confirmed by our hands (performance). There is a sense in which this is true, but it begs the question of “why” our predecessors in the faith begin with the heart.
Simply put, a “perfect heart” (one rooted in the intention to fulfill the two great commandments) creates the disposition for subsequent behavior. A “perfect heart” generates the will to engage in the concrete actions that achieve the goal (always by grace). And finally, a “perfect heart” establishes the basis for conviction, so that when we drift from our desire, the Holy Spirit has room to enter our lives and set us back on the right path.
When our hearts are not what they should be, we lose the basis for all of these things, and more. Behavior is not subject to evaluation. The will is not connected to any aim. And there is far less room for God to get our attention about the attitudes and actions which are sinful or careless.
When we “live from the heart” we have established the trajectory for trust and the basis for behavior. We have also made our core reality a dwelling place for the Risen Christ, and “from the heart” he will guide us into actions that glorify God and help others.