A.T. Robertson Commentary Mark 6:10

"And he said unto them, Wheresoever ye enter into a house, there abide till ye depart thence." — Mark 6:10 (ASV)

There abide (εκε μενετε). So also Mt 10:11; Luke 9:4. Only Matthew has city or village (10:11), but he mentions house in verse 12. They were to avoid a restless and dissatisfied manner and to take pains in choosing a home. It is not a prohibition against accepting invitations.