The main purpose of cemetery visits is to honor the deceased and to pray for the elevation of his or her soul. There is a custom also to visit the graves of the ancestors and righteous people to pray in times of trouble or in decisive moments of life. However, it is forbidden to pray to the dead or to ask anything from them (Deuteronomy 18:11). One should pray only to God requesting mercy in the merit of those who dwell in the dust. Therefore, as a rule, one should not request anything from the deceased. However, some rabbinical authorities permit people to ask the deceased to intercede in the Heaven and to pray to God as their representative — Melitz Yosher / מליץ יושר (a Gut Better / אַ גוטע בעטער in Yiddish).
As was mentioned previously, it is forbidden to recite blessings, study Torah or recite the Psalms, etc., within Arba Amot / ארבע אמות — four cubits of a grave, unless it is done in honor of the deceased. The customary recitation of Psalms by the graveside is clearly done in honor of the deceased and is, therefore, permissible.
Those who have not seen Jewish graves within the past thirty days should recite the special blessing, as explained earlier. When praying at the graveside, it is customary to place the left hand on the gravestone. Some have a custom to start the prayer with the following verses from the Book of Isaiah:
וְנָחֲךָ יְיָ תָּמִיד
וְהִשְׂבִּיעַ בְּצַחְצָחוֹת נַפְשֶׁךָ
וְהָיִיתָ כְּגַן רָוֶה
וּכְמוֹצָא מַיִם אֲשֶׁר לא יְכַזְּבוּ מֵימָיו׃
מוֹסְדֵי דוֹר וָדוֹר
וְקרָא לְךָ גּדֵר פֶּרֶץ
מְשׁבֵב נְתִיבוֹת לָשָׁבֶת׃
And the Lord will always guide you,
and satisfy your soul in scorched places,
and resurrect your bones;
And you will be like a watered garden,
and like a spring of waters that never fail.
From you [i.e., your good deads] will rebuild
the ancient ruins;
The generations-old foundations
you will re-establish;
They will call you "the repairer of the breach,
the restorer of the ways of civilization".
תשכב בשלום עד בא
מנחם משמיע שלום׃
Rest in peace until the coming of
the Consoler Who will proclaim peace
During the graveside visits, some have a custom to recite the following seven Psalms for the elevation of the departed soul: Psalms 33, 16, 17, 72, 91, 104 and 130. Some also recite verses from Psalm 119 that begin with the letters of the first name of the deceased (and sometimes the father’s or mother’s name, depending on the local custom). Afterwards, the custom is to recite those verses whose initial letters spell the word Neshamah / נשמה — the soul. Psalm 119 is organized in alphabetical order and sometimes called Alpha Beta. Some have a custom to recite additional prayers and supplications, especially when visiting the grave of a parent, and conclude the visit with the memorial prayer. In presence of a Minyan / המניין — a quorum of at least ten Jewish men over the age of thirteen required for public prayer, the Mourner's Kaddish / קדיש יתום is also recited.