John Piper from This Momentary Marriage:
Marriage is not mainly about prospering economically; it is mainly about displaying the covenant-keeping love between Christ and his church. Knowing Christ is more important than making a living. Treasuring Christ is more important than bearing children.
If we make secondary things primary, they cease to be secondary and become idolatrous. They have their place. But they are not first, and they are not guaranteed. Life is precarious, and even if it is long by human standards, it is short. “What is your life? For you are a mist that appears for a little time and then vanishes” (James 4:14). “Do not boast about tomorrow, for you do not know what a day may bring” (Prov. 27:1).
It may have many bright days, or it may be covered with clouds. If we make secondary things primary, we will be embittered at the sorrows we must face. But if we set our face to make of marriage mainly what God designed it to be, no sorrows and no calamities can stand in our way. Every one of them will be, not an obstacle to success, but a way to succeed. The beauty of the covenant-keeping love between Christ and his church shines brightest when nothing but Christ can sustain it.
(HT: Rick Ianniello)