I asked how we can realistically put these teachings into practice. Let's see what R' Twerski has to say about this in his commentary. He starts out with a story about two brothers who were Chassidic masters:
[They] would travel from town to town to encourage people to greater devotion to Torah study and mitzvos. They appeared as itinerant poor people, and no one showed them any particular warmth. ...In one own they were well received by a particular melamed (tutor). Years later, when their fame as tzaddikim had spread, they again came to this town, but this time they came in an impressive horse-drawn carriage. The town's most prominent citizen greeted them and invited them to his spacious home. [One of the brothers] politely declined the invitation. "During the years we came as unknown wanderers," he said, "you never welcomed us. We have not changed, and the only reason you invite us now is because we came in an impressive carriage. You may then take the horses and carriage to your home, and we will stay with the melamed, who accepted us for who we were."R' Twerski continues by referring to Abraham, who welcomed three strangers into his home who were revealed to be angels. The author of the book of Hebrews seemed to think this could happen to any of us:
Do not forget to entertain strangers, for by so doing some people have entertained angels without knowing it. (Hebrews 13:2)So I guess this is the first practical bit of advice on how to have a open house, Jewish-style: don't discriminate against strangers.