Allah named the spouse-relationship as one of His ăyăt (signs). Three structural elements: sakīnah (tranquility), mawaddah (love), raḥmah (mercy).

Sūrah al-Rūm verse 21 is the structural foundation of Islamic marriage-theology. Allah said: 'wa-min ăyătihi an khalaqa lakum min anfusikum azwăjan li-taskunū ilayhă wa-jaʿala baynakum mawaddatan wa-raḥmah; inna fī dhălika la-ăyătin li-qawmin yatafakkarūn'. And of His signs is that He created for you spouses from yourselves, that you may find tranquillity in them; and He placed between you love and mercy; indeed in this are signs for those who reflect. Read each clause carefully. 'wa-min ăyătihi'. And of His signs. The verse opens by naming the marriage-relationship as one of Allah's ăyăt. The Arabic ăyăt are signs that point to Allah's existence, attributes, and design. The marriage is named alongside the sun, the moon, the night and day, the rain, the cycles of life and death, the diversity of human languages and skin colors (the surrounding verses of Sūrah al-Rūm). The marriage is in this elevated category: a structural sign of Allah's mercy and design. 'an khalaqa lakum min anfusikum azwăjan'. That He created for you spouses from yourselves. The Arabic min anfusikum (from yourselves) indicates the spouse is structurally of the same kind as the believer, not a subordinate or lesser being; the partner is from the same essence. 'li-taskunū ilayhă'. That you may find tranquillity in them. The Arabic verb sakana is to dwell, to come to rest, to settle; the same root as masjid (place of prayer-dwelling) and Sakīnah (the divine tranquility). The marriage is structurally a place of rest. The home is meant to be where the believer comes to rest; the spouse is meant to be the partner in whom rest is found. 'wa-jaʿala baynakum mawaddatan wa-raḥmah'. And He placed between you love and mercy. The Arabic mawaddah is loving affection, the romantic-emotional bond between spouses. Raḥmah is mercy, the compassion that softens hearts toward each other. The classical scholars distinguished the two: mawaddah is the warm affection that characterizes the relationship at its peak (the romantic days, the moments of close intimacy, the seasons of mutual delight); raḥmah is the deeper compassion that sustains the relationship through difficult times (illness, aging, conflicts, hardships). The two together are the structural complement; mawaddah alone (without raḥmah) cannot sustain a marriage through life's difficulties; raḥmah alone (without mawaddah) becomes a duty-relationship without joy. Allah placed both in the marriage He designed. 'inna fī dhălika la-ăyătin li-qawmin yatafakkarūn'. Indeed in this are signs for those who reflect. The verse closes by naming the audience: those who reflect. The marriage's structural design is a sign of Allah for those who pause to consider it. Now consider modern application. Many Muslim marriages, in the modern strain, lose track of the three elements. Sakīnah is eroded by stress, by phones, by competing priorities; the home becomes a place of irritation rather than rest. Mawaddah dims after the first years of romantic intensity; the spouses become more like co-managers of a household than lovers. Raḥmah is tested in the moments of conflict, illness, or aging; without the structural mercy-disposition, the marriage cracks under pressure. The cure has three motions. First, restore sakīnah. Make the home a place of rest. Reduce noise (the phones, the social media, the constant input). Increase peace (prayer together, meals together, silence shared). Sakīnah is built by structural practices that create rest. Second, restore mawaddah. The Prophet ﷺ modeled marriage-warmth in ways that should reshape every Muslim marriage. He raced ʿĀʾishah; he kissed her while fasting (the kiss did not break the fast for those whose discipline was assured); he sat with her in conversation; he spoke of his love for her openly. The Sunnah of mawaddah-expression includes verbal expressions of love, physical affection, time together, gifts. Where the marriage has lost mawaddah, deliberate restoration is required. Third, cultivate raḥmah. The marriage will face difficulty; the spouse will be irritating; the conflicts will arise; without structural mercy, these accumulate into resentment. The mercy-discipline includes: forgiving small wrongs without holding them; speaking with patience even when frustrated; serving without keeping score; loving the partner across the seasons of the relationship. Pray today: Allāhumma 'ajʿal baytī maskanan li-l-sakīnah, mam-lūʺ an bi-l-mawaddah, mu-ḥăṭan bi-l-raḥmah, ăyatan min ăyătika. O Allah, make my home a dwelling of tranquility, filled with affection, surrounded with mercy, a sign of Your signs. The verse names the design; the believer lives the three; the marriage is one of Allah's ayăt in the believer's own home.