§ 3. (I.) It is not improper to illustrate a little the manner in which we have described this duty of meditation, or the considering and contemplating of spiritual things. It is confessed to be a duty by all, but practically denied by most. Many that make conscience of other duties, easily neglect this; they are troubled if they omit a sermon, a fast, or a prayer in public or private; yet were never troubled that they have omitted meditation perhaps all their lifetime to this very day; though it be that duty, by which all other duties are improved, and by which the soul digesteth truths for its nourishment and comfort. It was God's command to Joshua, _This book of the law shall not depart out of thy mouth, but thou shalt meditate therein day and night, that thou mayest observe to do according to all that is written therein_.[348] As digestion turns food into chyle and blood, for vigorous health; so meditation turns the truths received and remembered into warm affection, firm resolution, and holy conversation. [Footnote 348] Joshua i, 8. § 4. This meditation is, the acting of all the powers of the soul. It is the work of the living, and not of the dead. It is the work of all others the most spiritual and sublime, and therefore not to be well performed by a heart that is merely carnal and earthly. They must necessarily have some relation to heaven, before they can familiarly converse there. I suppose them to be such as have a title to rest, when I persuade them to rejoice in the meditations of rest. And supposing thee to be a Christian, I am now exhorting thee to be an active Christian. And it is the work of the soul I am setting thee to, for bodily exercise doth here profit but little. And it must have all the powers of the soul, to distinguish it from the common meditation of students; for the understanding is not the whole soul, and therefore cannot do the whole work. As in the body, the stomach must turn the food into chyle, and prepare for the liver; the liver and spleen turn it into blood, and prepare for the heart and brain; so in the soul, the understanding must take in truths, and prepare them for the will, and that for the affections. Christ and heaven have various excellencies, and therefore God hath formed the soul with different powers for apprehending those excellencies. What the better had we been for odoriferous flowers, if we had no smell? Or what good would language or music have done us, if we could not hear? Or what pleasure should we have found in meats and drinks, without the sense of taste? So, what good could all the glory of heaven have done us, or what pleasure should we have had in the perfections of God himself, if we had been without the affections of love and joy? And what strength or sweetness canst thou possibly receive by thy meditations on eternity, while thou dost not exercise those affections of the soul, by which thou must be sensible of the sweetness and strength? It is the mistake of Christians,