The term “grumbling” speaks to dissatisfaction in the heart on account of the guest in the home and so stands in contrast to the command of 1 Peter 4:8 to “keep loving one another earnestly.” It is possible to open your home to a destitute brother or sister (perhaps one known to be guilty of sin) without opening your heart to that person. Peter’s reference to “without grumbling” goes deeper than an audible muttering and penetrates to the attitude of the heart. We might say that as God has graciously given his chosen ones a place in his family (contrary to merit), so his people need to give space graciously to another.
9 Show hospitality to one another without grumbling.