Question: I have heard that there is an obligation to provide a guest not only with food, drink and lodging but with safe escort as well. I can see how the first three can be accomplished but find it difficult to leave my home and provide my guest with safe escort until his destination. What is the right thing to do?
Answer: It is customary to escort a guest for a short distance outside your home. This is based on a statement in the Talmud (Mesechta Sota 46b) that one who escorts his guest four cubits in the city ensures that he will meet no harm.
Maharsha (ibid. 45b) explains that this protection is supernatural. King David has taught us that "He fulfills the wishes of those who fear Him" (Tehillim 145:19). By escorting a guest even that short distance, you demonstrate a desire for him to be protected and G-d fulfills your desire by finishing the job. He also suggests that the angels which steadily accompany the host finish the job for him by carrying on the escort which he began.
So taking that short walk with your guest is not only a little exercise in physical fitness but a major exercise of faith.