From Paul Tripp’s What Did You Expect?:

God places lilies next to rocks. He places trees next to streams. He causes bright sun to follow a dark night. He made the muscles of a lion and the delicacy of the wing of a hummingbird. One way God establishes beauty is by putting things that are different next to each other. Isn’t this exactly what God does in marriage? He puts very different people next to each other. This is how he establishes the beauty of a marriage. The moon would not be so striking if it hung in a white sky; in the same way, the striking beauty of a marriage is when two very different people learn to celebrate and benefit from their differences and to be protected from their weaknesses by being sheltered by the other’s strength.