Question:

Can one be menachem avel  (comfort the mourner) over the phone?

Discussion:

The Rambam writes that there are two aspects of nichum aveillim; the first one is to comfort the mourners in their time of distress over the loss of their relative. This is done by expressing sympathy and consoling them over their loss. The other aspect of the mitzvah is to elevate the nishama of the departed person.

One can fulfill the first aspect of the mitzvah merely by being in the house of mourning even without saying anything (Moed Katan 21b). To fulfill the second aspect of the mitzvah it is necessary to visit the home of the deceased (Shabbos 152a).

Rav Moshe zt”l writes (O.C. 4:40:11) That while it is possible to comfort a mourner over the phone, it is not possible to elevate the soul of the deceased without actually coming to the house of mourning. Additionally, a phone call may not be the most respectful way of comforting the mourner. Therefore, if one can visit the mourner in person he should do so. However, if it is not possible to visit the mourner then a phone call would be the next best option.

Nichum Aveillim on Shabbos

The accepted custom is not to comfort a mourner on Shabbos or Yom Tov (Aruch Hashulchan O.C. 287:3). If one would be unable to be menachem him during the week then it may be done on Shabbos (ibid 1). The Kaf Hachaim (O.C. 287:4) writes that when one is menachem avel on Shabbos he should not say any explicit words of nechama and should keep his visit to a short amount of time.