So the wisdom of Jesus is that we should “lay up for ourselves treasures in heaven”…where forces of nature and human evil cannot harm what we treasure. That is to say, direct your actions toward making a difference in the realm of spiritual substance sustained and governed by God. Invest your life in what God is doing, which cannot be lost. Of course, this means that we will invest in our relationship to Jesus himself, and through him to God. But beyond that, and in close union with it, we will devote ourselves to the good of other people—those around us withing range of our power to affect. These are among God’s treasures. “The Lord’s portion,” we are told, “is his people” (Duet. 32:9). And that certainly includes ourselves, in a unique and fundamental way. We have the care of our own souls and lives in a way no one else does, and in a way we have the care of no one else.
And we also care for this astonishingly rich and beautiful physical realm, the earth itself, of which both we and our neighbors are parts. “You have established the earth and it continues. All things stand this day according to your directions. Far all things are your servants” (Ps. 119:91). God himself loves the earth dearly and never takes his hands off it. And because he loves it and it is good, our care of it is also eternal work and a part of eternal life.
…This is a large part of what the apostle Paul calls “sowing to the spirit.” And, when we do such sowing, “of the spirit we reap what is everlasting.” So “let us not lose heart in doing good,” he continues, “for when the time is right we shall reap, if we don’t quit. Therefore as we have opportunities let us do good to all men, and most of all to the family of faith” (Gal. 6:8-10). This is, precisely, how we deposit treasures in heaven on a daily, hourly basis. (Dallas Willard, The Divine Conspiracy, p. 205-6)