Eph 5:9 (for the fruit of the Spirit is in all goodness, righteousness, and truth),
The second point the apostle makes in walking in the light is displayed in a life of Righteousness which means moral integrity and rightness. This fights all disorders and injustices. God put you in your marriage to refine and conform you into His image by making you righteousness and growing you in it. God is glorified when you honor your spouse by living a life of integrity and character.
This is followed by his third point, life of Truth. To walk in the light is to live in truth which means moral reality, honesty, sincerity, and straightforwardness, as opposed to all that is false. Where there is no honesty, sincerity or straightforwardness, marriage suffers. God desires truth in the inward parts, and He knows that naturally we are deficient of it. He therefore puts truth into our hearts by Christ the truth dwelling in us.
We can have glorious marriages when we walk in the light of goodness, righteousness, and truth. In summary, all Christian morality lies in the good, the right, and the true.