Heavenly minded; no earthly good?

Third, they are those who, from the love that is in them, are, in heart and life, in principle and practice, struggling after holiness. Holy love makes them long for holiness. It is a principle that thirsts after growth. It is in imperfection, and in a state of infancy, in this world, and it desires growth. It has much to struggle with. In the heart in this world there are many opposite principles and influences; and it struggles after greater oneness, and more liberty, and more free exercise, and better fruit. The great strife and struggle of the new man is after holiness. His heart struggles after it, for he has an interest in heaven, and therefore he struggles with that sin that would keep him from it. He is full of ardent desires, and breathings, and longings, and strivings to be holy. And his hands struggle as well as his heart. He strives in his practice. His life is a life of sincere and earnest endeavor to be universally and increasingly holy. He feels that he is not holy enough, but far from it; and he desires to be nearer perfection, and more like those who are in heaven. And this is one reason why he longs to be in heaven, that he may be perfectly holy. And the great principle which leads him thus to struggle, is love. It is not only fear; but it is love to God, and love to Christ, and love to holiness. Love is a holy fire within him, and, like any other flame which is in a degree pent up, it will and does struggle for liberty; and this its struggling is the struggle for holiness.

Fifth, If you would be in the way to the world of love, see that you live a life of love-of love to God, and love to men. All of us hope to have part in the world of love hereafter, and therefore we should cherish the spirit of love, and live a life of holy love here on earth. This is the way to be like the inhabitants of heaven, who are now confirmed in love forever. Only in this way can you be like them in excellence and loveliness, and like them, too, in happiness, and rest, and joy. By living in love in this world you may be like them, too, in sweet and holy peace, and thus have, on earth, the foretastes of heavenly pleasures and delights. Thus, also, you may have a sense of the glory of heavenly things, as of God, and Christ, and holiness; and your heart be disposed and opened by holy love to God, and by the spirit of peace and love to men, to a sense of the excellence and sweetness of all that is to be found in heaven. Thus shall the windows of heaven be as it weere opened, so that its glorious light shall shine in upon your soul. Thus you may have the evidence of your fitness for that blessed world, and that you are actually on the way to its possession. And being this made meet, through grace, for the inheritance of the saints in light, when a few more days shall have passed away, you shall be with them in their blessedness forever. Happy, thrice happy those, who shall thus be found faithful to the end, and then shall be welcomed to the joy of their Lord! There "they shall hunger no more, neither thrist anymore; neither shall the sun light on them, nor any heat. For the lamb which is in the midst of the throne shall feed them, and lead them to living fountains of waters, and God shall wipe away all tears from their eyes."

Jonathan Edwards, Heaven, a World of Love

 Edwards in these passages expresses how it is that true heavenly-mindedness does not lead to escapism and dereliction of  duty in the present life, but rather invigorates and enhances the Christian's ability to be of great good in the present life. For in longing for heaven, the heart it drawn to its fruits, the desire for which causes within the heart a pursuit of holiness and charity, which are the fruits of heaven. The greater lack of these constitutes the greater lack of heaven, but the greater pursuit of these brings heaven the closer to the experience of the Christian. If the Christian should wish to experience the joys of heaven--wherein no lack of love and no striving against others is found--he must pursue selfless love and beneficent service to his neighbor, and thus to God. The love of God compels us to live as He lives, full of grace and truth. How could a greater measure of such fruits lead to a lesser effort for good in the present life? The contrary is the case, and it is both a shame upon the Church in her failures to conceive of heaven rightly, and condemnation upon her enemies, whose slander is based upon the errors they see rather than the truth that stares them in the face.