Begin by reading Romans 12:13 and Hebrews 13:2.
Hospitality… is the will of God for you. God commands you to be hospitable. …He calls you to be hospitable because he himself is a welcomer of strangers and loves the sojourner.
…Throughout history, God has called his people to welcome outsiders into their cities, homes, and lives. Israel was commanded to practice hospitality with their Jewish neighbors but also to welcome, care for, and bless those who visited their cities. Likewise, the church is also commanded to welcome both believers and unbelievers.
…The most basic idea behind hospitality is to care for outsiders in a way that you would care for insiders. You welcome them. So, when was the last time you invited outsiders into your home? Into your busy life? Outsiders are not those close to you but those who are not yet a part of your life. This includes people at church you have not taken the time to meet as well as your neighbors and coworkers you do not yet know. They may be outside or inside the kingdom, but they are currently outside of your ministry influence.
Of course there is no better picture of hospitality than what we find in the gospel, for in the gospel God calls those who were not his people, ‘My people.” By faith we are orphans who have been adopted into God’s family, made coheirs with Christ, and are promised a place at his table in the kingdom to come. God has accepted you and welcomed you in Christ. You know what it is to be an outsider and yet received as an insider, so you should be ready to show others what that kind of grace looks like on a smaller scale in your home.
Taken from Chap.22 “Welcome” (found in Part Two, “The Gospel and Others”) in Note to Self: The Discipline of Preaching to Yourself by Joe Thorn (Crossway, 2011), pp.81-82.