“And again I say, Rejoice” (Phil. 4:4).
It is a good thing to rejoice in the Lord. Perhaps you have tried this, and the first time seemed to fail. Never mind, keep right on and when you cannot feel any joy, when there is no spring, and no seeming comfort and encouragement, still rejoice, and count it all joy. Even when you fall into divers temptations, reckon it 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 coolly 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, and you will find your heart all exhilarated and refreshed by the fullness within. Lord teach me to rejoice in Thee, and to “rejoice evermore.” –Selected

“The weakest saint may Satan rout,
Who meets him with a praiseful shout.”

“Be filled with the Spirit…singing and making melody in your heart to the Lord” (Eph. 5:18-19).
Here the Apostle urges the use of singing as one of the inspiring helps in the spiritual life. He counsels his readers not to seek their stimulus through the body, but through the spirit; not by the quickening of the flesh, but by the exaltation of the soul.

“Sometimes a light surprises
The Christian while he sings.”

Let us sing even when we do not feel like it, for thus we may give wings to leaden feet and turn weariness into strength. –J. H. Jowett
“At midnight Paul and Silas prayed, and sang praises unto God: and the prisoners heard them” (Acts 16:25).
Oh, Paul, thou wondrous example to the flock, who could thus glory, bearing in the body as thou didst “the marks of the Lord Jesus”! Marks from stoning almost to the death, from thrice beating with rods, from those hundred and ninety-five stripes laid on thee by the Jews, and from stripes received in that Philippian jail, which had they not drawn blood would not have called for washing! Surely the grace which enabled thee to sing praises under such suffering is all-sufficient grace. –J. Roach

“Oh, let us rejoice in the Lord, evermore,
When darts of the tempter are flying,
For Satan still dreads, as he oft did of yore,
Our singing much more than our sighing.”