“And when ye come into an house, salute it.”
Matthew 10:12 — Greek Interlinear
Church Fathers on Matthew 10:12
The Lord had said above, 'The workman is worthy of his meat;' that they should not hence suppose that He would open all doors to them, He here commands them to use much circumspection in the choice of a host, saying, 'Into what city or town ye enter, enquire who in it is worthy.'
The Apostles, on entering a strange town, could not know of each inhabitant what sort of man he was; they were to choose their host therefore by the report of the people, and opinion of the neighbours, that the worthiness of the preacher might not be disgraced by the ill character of his entertainer.
The Apostles are not to choose carelessly the house into which they enter, that they may have no cause for changing their lodging; the same caution is not enforced upon the entertainer, lest in choosing his guests, his hospitality should be diminished.