One is obligated to stand in honor of his parent when the parent enters the room. As soon as one’s father or mother enters the room and is visible, one is required to stand as an expression of honor and to remain standing until the parent sits down or arrives at the place where he or she will remain. This obligation applies to both sons and daughters, and, as mentioned, it requires standing for both a father and a mother.
How many times over the course of the day must one stand to honor his parents? If a person sees his father or mother many times over the course of the day, must he stand each and every time his father or mother enters the room?
This issue appears to be subject to a debate among the Rishonim (Medieval Halachic authorities). When it comes to the parallel obligation to stand in honor of one’s Rabbi, the Rambam (Rabbi Moshe Maimonides, Spain-Egypt, 1135-1204) ruled that one is obligated to stand only once each day and once each night. If a person sees his Rabbi several times over the course of the day, he does not have to stand in the Rabbi’s honor each time; after he has stood once to show honor to the Rabbi, he does not have to stand again that day. From the rulings of the Rif (Rabbi Yishak of Fez, Morocco, 1013-1103) and the Rosh (Rabbenu Asher Ben Yehiel, Germany-Spain, 1250-1327), however, it appears that one must stand whenever his Rabbi enters the room, even if this happens dozens of times throughout the day.
In the context of standing for one’s Rabbi, the Shulhan Aruch follows the view of the Rif and the Rosh, requiring one to stand whenever he sees his Rabbi, even if his happens one hundred times a day. Since the Poskim (Halachic authorities) generally equate the laws of Kibud Horim (honoring parents) with those of Kebod Rabo (honoring one’s Rabbi), we must conclude that one is obligated to stand whenever he sees his father or mother, even if this happens many times throughout the day. This is, indeed, the Halacha for Sepharadim, who follow the rulings of the Shulhan Aruch. (Ashkenazim, however, follow the Rambam’s position in this regard, and for them it suffices to stand only once each day and once each night.)
Of course, this could pose considerable difficulty in a situation of a parent and child who work together, and the parent enters the child’s room many times over the course of the day. In such a case, it is advisable for the child to ask the parent to wave this obligation of honor, so that he or she does not have to stand each and every time the parent enters the room. Once the parent grants Mehila (waving of the rights), then the child should stand for the parent just once in the daytime and once at night to fulfill the Misva, but would not have to stand for the parent besides those times.
Summary: According to Sephardic practice, one is obligated to stand each and every time his or her parent (father or mother) enters the room. If this poses difficulty, one may ask the parent to wave this obligation, and if the parent agrees, then it suffices to stand in the parent’s honor just once each day and once each night to fulfill the Misva.
