A.B. Simpson emphasizes the importance of rejoicing in the Lord, even in times of difficulty and temptation. He encourages believers to persist in joy, regardless of their circumstances, trusting that God will sustain them and fill their hearts with gladness through the Holy Spirit. Simpson assures that true joy is a source of strength for God's people, capable of transforming sorrow into gladness. He calls for a continual attitude of rejoicing, teaching that joy is essential for spiritual victory and resilience. Ultimately, he seeks to inspire a deeper reliance on God's joy as a refreshing fountain in life's wilderness.

It is a good thing to rejoice in the Lord. Perhaps you found the first dose ineffectual. Keep on with your medicine, and when you cannot feel any joy, when there is no wellspring and no seeming comfort and encouragement, still rejoice, and count it all joy. Even when you fall into temptations, reckon the circumstance joy and delight, and God will make your reckoning good. Do you suppose your Father will let you carry the banner of His victory and His gladness on to the front of the battle, and then cooly stand back and see you captured or beaten back by the enemy? Never! The Holy Spirit will sustain you in your bold advance and fill your heart with gladness and praise. You will experience an exhilaration and refreshing because of the fullness of His Spirit within. Lord, teach me to rejoice in Thee, and to rejoice evermore. The joy of the Lord is the strength of His people, The sunshine that scatters their sadness and gloom; The fountain that bursts in the desert of sorrow, And sheds o'er the wilderness, gladness and bloom.