סימן ק סעיף כב
אוֹנֵן אֵינוֹ נוֹשֵׂא אֶת כַּפָּיו. וְאָבֵל תּוֹךְ שְׁנֵים עָשָׂר חֹדֶשׁ עַל אָבִיו וְאִמּוֹ אוֹ תוֹךְ שְׁלֹשִׁים עַל שְׁאָר קְרוֹבִים, אֵינוֹ נוֹשֵׂא אֶת כַּפָּיו, וְצָרִיךְ לָצֵאת מִבֵּית הַכְּנֶסֶת קֹדֶם רְצֵה עַד אַחַר נְשִׂיאַת כַּפָּיִם. וְאִם אֵין בְּבֵית הַכְּנֶסֶת שְׁנֵי כֹּהֲנִים אֲחֵרִים, מֻתָּר לְאָבֵל לִשָּא אֶת כַּפָּיו תּוֹךְ שְׁנֵים עָשָׂר חֹדֶשׁ עַל אָבִיו וְאִמּוֹ וְתוֹךְ שְׁלֹשִׁים עַל שְׁאָר קְרוֹבִים. אֲבָל תּוֹךְ שִׁבְעָה, כְּגוֹן הַקּוֹבֵר מֵתוֹ בָּרֶגֶל, אֲפִלּוּ אִם אֵין שָׁם שְׁנֵי כֹּהֲנִים אֲחֵרִים, אֵינוֹ נוֹשֵׂא אֶת כַּפָּיו (קכ"ח).
A mourner, before burial takes place, may not raise his hands.61Even on Yom Tov, when the laws pertaining to the mourning period do not take effect. (see Chapter 198) He may not duchan because he is not in a state of happiness. (Magein Avraham, Mishnah Berurah 128:158) A mourner, during the twelve months of mourning for his father or mother, or, during the thirty days of mourning for other relatives, may not raise his hands.62If he were called upon to duchan, he should not go up. (Peri Chadash) If he went up, he does not have to step down. (Rav Ephraim Zalman Margalios Z“l [Laws of Onein], Ba’eir Heiteiv, Peri Chadash) The Peri Megadim 128:64 says he should step down. The Mishnah Berurah 128:158 seems to be inclined to say if he were called upon, he should go up, but he also mentions the ruling of Peri Chadash, also see Chayei Adam. He must leave the synagogue before Retzeih is said, and stay outside until after Birkas Kohanim. In the event there are no other kohanim in the synagogue, the mourner is permitted to raise his hands during the twelve month period of mourning, for his father or mother, or during the thirty days of mourning for other relatives. But during the seven days of mourning, for example, if he buried his dead on the Festival, even if there are no other kohanim, he may not raise his hands to bless the people.
תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)