373. A Kohein Who Drank Wine

Tefillah u’Birkas Kohanim 15:4

Immaturity means that a young kohein should not duchen until his facial hair grows in. Intoxication means that a kohein who drank a reviis of wine at one time should not duchen until the wine’s effects wear off. This is because of the aforementioned connection between blessing and performing the Temple service. (See Halacha 15:3.) If a kohein drank a reviis of wine in two instances, or if he mixed a little water in it, he is permitted to duchen. If he drank more than a reviis, he may not duchen until the wine’s effects wear off. This is so even if he drank it discontinuously or diluted with water. The volume of a reviis is 2 thumbs x 2 thumbs x 2 7/10 thumbs. (Practically speaking, this is in the vicinity of three ounces.)

Tefillah u’Birkas Kohanim 15:5                                                           

Ritual impurity of the hands refers to a kohein who did not wash his hands. In order to duchen, a kohein must wash his hands to the wrist as was done when sanctifying the hands for the Temple service as per Psalms 134:2, “Raise your hands in holiness and bless God.” A chalal* does not duchen because he is not a kohein.

*Chalal - the offspring of a kohein with a woman not permitted to him.