In Greco-Roman culture, hospitality was thought of somewhat differently than we think of it today; it was understood to be a “mark of culture” and “a basic aspect of civilized behavior” (S. C. Barton, “Hospitality,” in Dictionary of the Later New Testament and Its Developments [Downers Grove: InterVarsity, 1997], 502):
“For [most Westerners today,] hospitality is personal and individualistic and has to do with entertaining relatives and friends with the prospect of the hospitality being reciprocated. In the first-century Mediterranean world, however, hospitality was a public duty toward strangers where the honor of the community was at stake and reciprocity was more likely to be communal rather than individual. Further, whereas contemporary Western hospitality has become secularized (so that a common synonym is “entertainment”), hospitality in antiquity was a sacred duty. (Ibid., 501-502)
In Jewish thought, hospitality is seen as rooted in both a concept of the Almighty who “loves the sojourner” (e.g., Deut 10:18), and in the story of the Israelites, to whom God said, “You shall not wrong a sojourner or oppress him, for you were sojourners in the land of Egypt” (Ex 22:21). The importance of hospitality is demonstrated positively in the stories of Abraham (Gen 18), Lot (Gen 19), Rebekah (Gen 24), and others; and negatively in the examples of Sodom (Gen 19) and Gibeah (Judg 19), among others.
In the NT era, hospitality was a practical issue: traveling believers relied upon other believers for lodging. Although inns were common, “most were far from ideal and some were no more than brothels. . . . In addition, they posed a number of dangers, including robbery and murder” (J. T. Fitzgerald, “Hospitality,” in Dictionary of New Testament Background [Downers Grove: InterVarsity, 2000], 523).
As well, however, Barton intriguingly suggests that
. . . hospitality, for Paul as for Jesus before him, is not just a practical issue. It is a fundamental expression of the gospel: a response to God’s hospitality to humankind in providing Christ as the “paschal lamb” (1 Cor 5:7) and an outworking of what it means to be members of the one “body of Christ” (Ibid., 503; emphasis added).
Not only is hospitality a fundamental expression of Christian faith, it is also a “fundamental outworking of love” (Ibid., 505). The connection drawn between brotherly love and hospitality in the NT is striking. In Paul, we find the two in the same context of Romans 12:10-12:
Love one another with brotherly affection. Outdo one another in showing honor. Do not be slothful in zeal, be fervent in spirit, serve the Lord. Rejoice in hope, be patient in tribulation, be constant in prayer. Contribute to the needs of the saints and seek to show hospitality.
In Peter, we find the connection drawn even more closely in 1 Peter 4:8-9, although we have here instead of “brotherly love” the more general “loving one another”:
Above all, keep loving one another earnestly, since love covers a multitude of sins.  Show hospitality to one another without grumbling.
And in Hebrews, we find hospitality as an example of brotherly love in 13:1-2:
Let brotherly love continue.  Do not neglect to show hospitality to strangers, for thereby some have entertained angels unawares.
These are the only three references to filozenia (hospitality) or the related adjective filozenos (hospitable) in the NT, other than the two instances in lists of necessary characteristics for elders (1 Tim 3:2; Tit 1:8 ) (a related term, zenodocheo, to be hospitable, is used as a characteristic for widows qualified to be supported by the church in 1 Tim 5:10; also zenidzo, to lodge someone, is used in Acts 10:6, 18, 23, 32; 21:16; 28:7; Heb 13:2), and in each of these instances, the concept of love for other believers is contextually close at hand. Stahlin notes that “agape [love] always implies filozenia [hospitality]” (G. Stahlin, “zenos, ktl.,” in TDNT 5:20).
The connection and contrast between “brotherly love” (filadelfia) and “hospitality” (filozenia, lit. “love of strangers“) is striking. It is, I think, a reminder that although a particular Christian might be a stranger to us, he is still a brother and should be treated as such.
Although we think today of hospitality as including having fellow believers from our church over for a meal — as good an idea as that might be — such an activity might not qualify as “hospitality” in the NT sense of the word, as it does not involve “strangers” — those who are not part of the local body. (Yes, 1 Peter 4:9 says to “show hospitality to one another,” but the widespread audience of 1 Peter must be kept in mind; cf. 1 Pet 1:1.)
On the other hand, putting up traveling believers would be, it appears, precisely the sort of thing the NT has in mind. While we (rightly) expect our spiritual leaders to be hospitable, we ought to remember that hospitality is incumbent upon all believers: Paul speaks to believers in general in Romans 12:13 when he says that we are to “pursue hospitality.” Some translations are too bland in translating the verb as “practice” (NAS, RSV). The verb here, dioko, connotes an earnest striving after something. “Part of the picture of the NT Christian is that he is always ready (Heb 13:2) to show hospitality, and to do so with zeal (Rom 12:13) and cheerfulness (1 Pet 4:9)” (Stahlin, 21).
And if the objection be lodged that hospitality was necessary in Paul’s day because of traveling conditions, but not in ours, we may respond with Marshall:
If the need today is less because of the existence of church buildings and hotels, we may still have to ask whether the practice was inherently helpful to the life of the church and whether the injunction in this verse [1 Pet 4:9] needs to be fulfilled not simply because it was practically necessary in the ancient world, but because it had spiritual value in its own right. (I. Howard Marshall, 1 Peter, IVPNTC [Downer's Grove: InterVarsity, 2003], 145)
So the next time someone comes in from out of town to speak at the church, consider whether you ought to see if you can host them at your house. Earnestly. Without grumbling. Even though the speaker might be your pastor’s peer, lodging him is not necessarily your pastor’s responsibility.