That holy affections are the essence of true spirituality can be seen from what God has commanded concerning our public worship. Jonathan Edwards argues that virtually all external expressions of worship “can be of no further use, than as they have some tendency to affect our own hearts, or the hearts of others” (115).

Consider, for example, the singing of praises to God, which seem “to be appointed wholly to excite and express religious affections. No other reason can be assigned, why we should express ourselves to God in verse, rather than in prose, and do it with music, but only, that such is our nature and frame, that these things have a tendency to move our affections” (115).

Some actually orchestrate worship in such a way that the affections of the heart are reined in and, in some cases, even suppressed. People often fear the external manifestation of internal zeal and love and desire and joy. Though they sing, they do so in a way that the end in view is the mere articulation of words and declaration of truths.

But if that were what God intended, why did he not ordain that we recite, in prose, biblical truths about him? Why sing? It can’t be simply for the aesthetic value of music or because of the pleasure it brings, for that would be to turn worship manward, as if we are now the focus rather than God. We sing because God has created not only our minds but also our hearts and souls, indeed our bodies as well, in such a way that music elicits and intensifies holy affections for God and facilitates their lively and vigorous expression.

The same may be said of how God operates on our souls in the preaching of his Word. Books and commentaries and the like provide us with “good doctrinal or speculative understanding of the things of the Word of God, yet they have not an equal tendency to impress them on men’s hearts and affections” (115). So, with a view to affecting sinners and not merely informing them, God has appointed that his Word be applied in a particularly lively way through preaching.

Therefore, when we think of how public worship should be constructed and what methods should be employed in the praise of God and the edification of his people, “such means are to be desired, as have much of a tendency to move the affections. Such books, and such a way of preaching the Word, and administration of ordinances, and such a way of worshiping God in prayer, and singing praises, is much to be desired, as has a tendency deeply to affect the hearts of those who attend these means” (121).

When people object that certain styles of public worship seem especially chosen for their capacity to awaken and intensify and express the affections of the heart, they should be told that such is precisely the God-ordained purpose of worship. What they fear, namely, the heightening and deepening of the heart’s desire and love for God, and the expansion and increase of the soul’s delight and joy in God, what they typically call “emotionalism” or even “manipulation”, is the very goal of worship itself. For God is most glorified in his people when their hearts are most satisfied (i.e., when they are most “affected” with joy) in him.