No one will suppose for a moment that the exhortation to rejoice can be applied in any sense to unbelieving men, to men of the world, to the ungodly. Granting that they have a joy peculiarly their own, it is of such a nature, and is so conditioned by the life of every day, that it would be cruel to bid them "rejoice _evermore_." The worldling has too many disappointments, struggles, and cares, for a permanent and unbroken joy such as that. He may think himself fortunate for rejoicings that come now and then! Besides, how could Paul recommend a rejoicing which is not "in the Lord," which is the only rejoicing possible to the unbeliever? Paul's joy is consistent with every duty of the religion he preached; but to that religion the unbeliever is opposed. His rejoicing cannot be acceptable to the Lord. It is spurious. It has no true, substantial source. To such a man the apostle might rather have said, "Weep!" Christian joy is an inheritance closely fenced around; and hard as it seems to enjoy any good things in which others cannot share, we must say, "Unbelieving men and women, it is not for you." The way here is through the strait gate, and along the narrow road. No joy can be "joy in the Lord" which does not contain the following elements-- 1. _Purity._ The objects that excite it must be pure. It must be free from all carnality and from all sin; it must spring from the soul's sympathy with God, with His truth, with His goodness. Holy in its objects, it becomes a sanctifying power. 2. _Calmness._ It is freedom from turmoil of heart, from disquietude of life. It suffuses our feeling and our conduct with peace--peace that "flows like a river." Hence, it is the condition of a quiet, steady Christian experience. 3. _Seriousness._ It does not depend on self-forgetfulness, or on a forced thoughtlessness. It is deepest in the most reflective, and is strengthened in all by an honest and habitual self-examination. 4. _Humility._ There is a sort of arrogance and self-sufficiency in worldly joy. Christianity puts man in his true place, and teaches him to refer all his peace to God. 5. _Love._ Love to man and to God; the latter as the natural effect of gratitude, the former from deep pity for his spiritual destitution, or from sympathy in a common experience of happiness. 6. _Permanence._ It is not a fitful, occasional, moody thing. Secondary sources of joy may fail, but God, the primary Source and Giver of all joy, remains; and the relationship between the believer and Him abides, so that the grounds of peace and of hope are everlasting.