“[Psalm 42:11] is an extraordinarily accurate picture of spiritual depression…you can almost see the man…the man who is dejected and disquieted and miserable, who is unhappy and depressed always shows it in his face. He looks troubled and he looks worried. You take one glance at him and you see his condition. Yes, says the Psalmist in effect, but when I really look at God, as I get better, my face gets better also.-‘He is the health of my countenance’. I lose that drawn, haggard, vexed, troubled, perplexed, introspective appearance and I begin to look composed and calm, balanced and bright. This is not the putting on of a mask, but something that is inevitable. If we are depressed or unhappy, whether we like it or not, we will show it in our face. On the other hand, if we are in the right relationship to God and in a true spiritual condition that again quite inevitably must express itself in our countenance, though I am not suggesting that we should perpetually have that inane grin upon our faces that some people think is essential to the manifestation of true Christian joy. You need not put anything on, it will be there; it cannot help expressing itself-‘He is the health of my countenance’.”
“Beloved Christian, whatever it is that is tending to get you down, tending to make you a victim of this anxiety, this morbid care, harassing and spoiling your Christian life and witness, whatever it is, let it be known unto God…and if you do so it is absolutely guaranteed that the peace of God…shall guard, keep, garrison your heart and mind…Like the Psalmist you will lay yourself down and you will sleep, you will know this perfect peace. Do you this, have you got this peace? Is this another bit of theory or does it actually happen? I assert that this is a fact. Read the stories of the saints and the martyrs and the Confessors…John George Carpenter, until a few years ago the General of the Salvation Army, tells how he and his wife had to part with their daughter, a lovely girl, of who they were so fond and proud and who had dedicated her young life to foreign mission work in the East. Suddenly she was taken ill with typhoid fever. Of course, they began to pray, but John Carpenter and Mrs. Carpenter somehow felt, although they could not explain it, that they could not pray for that child’s recovery. They went on praying but their prayer was-‘Thou canst heal her if Thou wilt’-they could not positively ask God to heal her…They went on like that for six weeks and then this beautiful girl died. The very morning she died John Carpenter said to Mrs. Carpenter, ‘You know, I am aware of a strange and curious calm within’, and she replied and said, ‘I feel exactly the same’. And she said to him, ‘This must be the peace of God’, And it was the peace of God…There they were, they had made their request known in the right way, and…this amazing calm and peace had come to them…’it must be the peace of God’. It was. Thank God for it.
“Never does the Apostle say that if we pray our prayer in and of itself will make us feel better. It is a disgraceful thing that people should pray for that reason. That is the psychologists’ use of prayer. They tell us that if we are in trouble it will do us good to pray…Prayer is not auto-suggestion.
Neither does he say, ‘Pray, because while you are praying you will not be thinking about that problem, and therefore you will have temporary relief’…Neither does he say, ‘If you fill your mind with thoughts of God and Christ these thought will push out the other things’…Neither does he say…’Pray, because prayer changes things’. No, it does not. Prayer does not ‘change things’…It is not your prayer that is going to do it, it is not you who are going to do it, but God. ‘The peace of God that passeth all understanding’-He, through it all, ‘will keep your hearts and minds in Christ Jesus.’
I must say a word about the expression ‘keeping’ your hearts and minds. It means garrisoning, guarding-a number of words can be used. It conjures up a picture. What will happen is that this peace of God will walk around the ramparts and towers of our life. We are inside, and the activities of the heart and mind are producing those stress and anxieties and strains from the outside. But the peace of God will keep them out and we ourselves inside will be at perfect peace. It is God that does it. It is not ourselves, it is not prayer, it is not some psychological mechanism. We make our requests known unto God, and God does that for us and keeps us in perfect peace.”
-From Martyn Lloyd-Jones’ Writings