Hospitality is enjoined in Hebrews 13, in Romans 12, and in 1 Peter 4.
In Hebrews 13:2:
2 Be not forgetful to entertain strangers: for thereby some have entertained angels unawares.
In Romans 12:13:
13 Distributing to the necessity of saints; given to hospitality.
In 1 Peter 4:9:
9 Use hospitality one to another without grudging.