Here’s a helpful passage from J. C. Ryle’s Holiness on counting the cost to be a Christian:
I am bold to say that it would be well if the duty of “counting the cost” were more frequently taught than it is. Impatient hurry is the order of the day with many religionists. Instantaneous conversions, and immediate sensible peace, are the only results they seem to care for from the Gospel. Compared with these all other things are thrown into the shade. To produce them is the grand end and object, apparently, of all their labours. I say without hesitation that such a naked, one-sided mode of teaching Christianity is mischievous in the extreme.
Let no one mistake my meaning. I thoroughly approve of offering men a full, free, present, immediate salvation in Christ Jesus. I thoroughly approve of urging on man the possibility and the duty of immediate instantaneous conversion. In these matters I give place to no one. But I do say that these truths ought not to be set before men nakedly, singly, and alone. They ought to be told honestly what it is they are taking up, if they profess a desire to come out from the world and serve Christ. They ought not to be pressed into the ranks of Christ’s army without being told what the warfare entails. In a word, they should be told honestly to “count the cost.”
Does any one ask what our Lord Jesus Christ’s practice was in this matter? Let him read what St. Luke records. He tells us that on a certain occasion “There went great multitudes with Him: and He turned and said unto them, If any come to Me, and hate not his father, and mother, and wife, and children, and brethren, and sisters, yea, and his own life also, he cannot be my disciple. And whosoever doth not bear his cross and come after Me, cannot be my disciple.” (Luke 14:25–27. I must plainly say, that I cannot reconcile this passage with the proceedings of many modern religious teachers. And yet, to my mind, the doctrine of it is as clear as the sun at noon-day. It shows us that we ought not to hurry men into professing discipleship, without warning them plainly to “count the cost.”
J. C. Ryle, Holiness: Its Nature, Hindrances, Difficulties and Roots (London: William Hunt and Company, 1889), 109–110.