For although to true religion there must indeed be something else besides affection, yet true religion consists so much in the affections that there can be no true religion without them.
He who has no religious affection is in a state of spiritual death, and is wholly destitute of the powerful, quickening, saving influences of the Spirit of God upon his heart. As there is no true religion where there is nothing else but affection, so there is no true religion where there is no religious affection. As, on the one hand, there must be light in the understanding as well as an affected fervent heart; where there is heat without light, there can be nothing divine or heavenly in that heart; so, on the other hand, where there is a kind of light without heat, a head stored with notions and speculations, with a cold and unaffected heart, there can be nothing divine in that light; that knowledge is no true spiritual knowledge of divine things. If the great things of religion are rightly understood, they will affect the heart. The reason why men are not affected by such infinitely great, important, glorious, and wonderful things, as they often hear and read of in the Word of God, is undoubtedly because they are blind; if they were not so, it would be impossible, and utterly inconsistent with human nature, that their hearts should be otherwise than strongly impressed, and greatly moved by such things.
Jonathan Edwards, The Religious Affections, chap 1 pp 49-50
High Plains Parson 