“Believers, if you would have an increase of happiness in Christ’s service, labor every year to grow in grace. Beware of standing still. The holiest men are always the happiest. Let your aim be every year to be more holy–to know more, to feel more, to see more of the fullness of Christ. Do not rest on old grace: do not be content with the degree of Christianity which you have attained. Search the Scriptures more earnestly; pray more fervently; hate sin more; mortify self-will more; become more humble the nearer you draw to your end; seek more direct personal communion with the Lord Jesus; strive to be more like Enoch– daily walking with God; keep your conscience clear of little sins; grieve not the Spirit; avoid arguments and disputes about the lesser matters of religion: lay more firm hold upon those great truths, without which no man can be saved. Remember and practice these things, and you will be more happy.”
Practical Religion, “Happiness”, 259.