Then said Jesus unto his disciples, If any man will come after me, let him deny himself, and take up his cross, and follow me. (Matthew 16:24)
It is common to think that the Christian life is one of comfort and blessing, resting in the assurance that God has saved us from our sins. That we prosper or we are assured of good things.
The Christian life is not one of ease, it is one of suffering. The challenges of everyday life are beset with opportunities for sin (Gen. 4:7). Striving against sin is, spiritually speaking, nothing but suffering and death. We err if we get comfortable in the war against the flesh. The Christian life is a battlefield and there are no foxholes to lay in for safety but for one: Christ. Yet, Christ is the one telling you to run headlong into the battle and make war on the flesh by His Spirit.
Calvin addresses this verse in the following way:
The patience of the saints, therefore, consists in bearing willingly the cross which has been laid on them. Luke adds the word daily — let him take up his cross Daily — which is very emphatic; for Christ’s meaning is, that there will be no end to our warfare till we leave the world. Let it be the uninterrupted exercise of the godly, that when many afflictions have run their course, they may be prepared to endure fresh afflictions.
The New Testament abounds with references to this suffering we will endure in the war against the flesh. Paul tells us elsewhere:
Now no chastening for the present seemeth to be joyous, but grievous: nevertheless afterward it yieldeth the peaceable fruit of righteousness unto them which are exercised thereby. (Hebrews 12:11)
Paul also shows us in Hebrews 11 the examples of the saints of the Old Testament, that they endured suffering for the sake of their inheritance in Christ. James tells us that we should “count it all joy” when we are met with afflictions, for it is God working patience in us and a desire for the world above (James 1:2-4).
It is an easy thing to believe in the perseverance of the saints and to turn that perseverance into presumption. Lest we fold the hands in rest against the war on the flesh, heed the words of John Owen in his masterful work The Mortification of Sin:
Do you mortify; do you make it your daily work; be always at it whilst you live; cease not a day from this work; be killing sin or it will be killing you.
This is what it means to take up the cross. Look to the Spirit of Christ to mortify the flesh (Romans 8:13). God has not promised us comfort in this life. He has promised us suffering and the power to overcome it. That is what it means to persevere.
I will conclude with the opening words of the Heidelberg Catechism:
Q. 1. What is thy only comfort in life and death?
A. That I with body and soul, both in life and death, am not my own, but belong unto my faithful Saviour Jesus Christ; who, with his precious blood, has fully satisfied for all my sins, and delivered me from all the power of the devil; and so preserves me that without the will of my heavenly Father, not a hair can fall from my head; yea, that all things must be subservient to my salvation, and therefore, by his Holy Spirit, He also assures me of eternal life, and makes me sincerely willing and ready, henceforth, to live unto him.