Martin Luther's Marriage

Life was hard. Family life was hard. Marriage was hard. And yet, Martin and Katie loved each other tremendously. They viewed marriage as a school of character, whereby God uses the hardships of daily family life to sanctify us.
...
May the marriage of Martin and Katie, as well as their love for their children, remind us today of Christ's love for his church and the Father's love for us as his redeemed children.

Source: Matthew Barrett - "Martin Luther on Marriage as a School of Character", Christian Living, The Gospel Coalition, 3 August 2011, https://www.thegospelcoalition.org/article/martin-luther-on-marriage-as-a-school-of-character