By way of general observation, I remark that our affections are engaged in religion. An oak--not as it stands choked up in the crowded wood, with room neither to spread nor breathe, but as it stands in the open field, swelling out below where it anchors its roots in the ground, and swelling out above where it stretches its arms into the air,--presents us with the most perfect form of firmness, self-support, stout and sturdy independence. So perfectly formed, indeed, is the monarch of the forest to stand alone, and fight its own battles with the elements, that the architect of the Bell Rock lighthouse is said to have borrowed his idea of its form from God in nature, and that, copying the work of a divine Architect, he took the trunk of the oak as the model of a building which was to stand the blast of the storm, and the swell of the winter seas. Observe, that although the state of the natural affections does not furnish any certain evidence of conversion, it is the glory of piety that these are strengthened, elevated, sanctified by the change. The lover of God will be the kindest, best, wisest lover of his fellow-creatures. The heart that has room in it for God, grows so large, that it finds room for all God's train, for all that He loves, and for all that He has made; so that the Church, with all its denominations of true Christians, the world, with all its perishing sinners, nay, all the worlds which He has created, find orbit-room to move, as in an expansive universe, within the capacious enlargement of a believer's heart. For while the love of sin acts as an astringent--contracting the dimensions of the natural heart, shutting and shriveling it up--the love of God expands and enlarges its capacity. Piety quickens the pulse of love, warms and strengthens our heart, and sends forth fuller streams of natural affection toward all that have a claim on us, just as a strong and healthy heart sends tides of blood along the elastic arteries to every extremity of the body. This new heart, however, mainly consists in a change of the affections as they regard spiritual objects. Without again traveling over ground which we have already surveyed, just look at the heart and feelings of an unconverted man. His mind being carnal, is enmity or hatred against God. This may be latent, not at first sight apparent, nor suspected, but how soon does it appear when put to the proof? Fairly tried, it comes out like those unseen elements which chemical tests reveal. Let God, for instance, by His providences or laws, thwart the wishes or cross the propensities of our unrenewed nature--let there be a collision between His will and ours--and the latent enmity flashes out like latent fire when the cold black flint is struck with steel.