This passage is part of a sermon by C.H. Spurgeon in 1866, and so it is a not a simple read, but will benefit any who will put in the time to understand.
“There is, a condition of mind which is even more sad than either spiritual deadness or known sin; it is a thorough, gradual, but certain decline of all the spiritual powers. Look at that consumptive man whose lungs are decaying, and in whom the vital energy is ebbing; it is painful to see the faintness which suffuses him after exertion, and the general languor which overspreads his weakened frame. Far more sad to the spiritual eye is the spectacle presented by spiritual consumptives who in some quarters meet us on all hands. The eye of faith is dim and overcast, and seldom flashes with holy joy; the spiritual countenance is hollow and sunken with doubts and fears; the tongue of praise is partially paralyzed, and has little to say for Jesus; the spiritual frame is lethargic, and its movements are far from vigorous; the man is not anxious to be doing anything for Christ; a horrible numbness, a dreadful insensibility has come over him.
If these spiritual consumptives hate sin, they do it so weakly that one might fear that they loved it still. If they love Jesus, it is so coldly that it is a point of question whether they love at all. If they sing Jehovah’s praises, it is very sadly, as if hallelujahs were dirges. If they mourn for sin, it is only with half-broken hearts, and their grief is shallow and unpractical. If they hear the Word of God they are never stirred by it; enthusiasm is an unknown luxury. If they come across a precious truth, they perceive nothing particular in it.
They throw themselves back upon the enchanted couch of sloth, and while they are covered with rags they dream of riches and great increase of goods. It is a sad, sad thing when Christians fall into this state; then indeed they need reviving, and they must have it, for “the whole head is sick and the whole heart faint.” Every lover of souls should intercede for declining professors that the visitations of God may restore them; that the Sun of righteousness may arise upon them with healing beneath his wings.”