In the days of the Temple in Jerusalem, Jewish priests were responsible for worship ceremonies and rituals, such as leading services, offering sacrifices, and burning incense. Learn about and Judaism's hereditary classes (caste system) - Kohanim and Levi'im - in the past and present.

Question: What is a Kohen?

Answer: Temple Priests

In the days of the Temple in Jerusalem, Kohanim (plural for Kohen) were priests responsible for worship ceremonies, such as leading services, offering sacrifices, burning incense and more. To maintain a high degree of purity, Kohanim observed certain prohibitions concerning marriage and contact with the deceased.

The High Priest

The High Priest, called HaKohen HaGadol, was the head of all the priests. He conducted services in the Temple on Yom Kippur, the holiest day of the Jewish year. And he was the only person allowed to enter the Holy of Holies, the holiest place in the Temple.

Today's Kohen

Today a Jew is considered a Kohen if he is a descendent of the first priest Aaron, the brother of Moses, from the Levi tribe.

In 1997, Dr. Karl Skorecki, a nephrologist and a top-level researcher at the University of Toronto and the Rambam-Technion Medical Center in Haifa, believed that if today's Kohanim are the descendants of one man (Aaron HaCohen), then they should have a common set of genetic markers at a higher frequency than the general Jewish population. Skorecki's study found that a particular marker (YAP-) was detected in 98.5 percent of the Kohanim, and in a significantly lower percentage of non-Kohanim. In addition, researchers found that a particular array of six chromosomal markers, called the Cohen Modal Hapoltype (CMH), was found in 97 of the 106 Kohenim tested. The chances of these findings happening at random is greater than one in 10,000. Thus, recent scientific research has proven a clear genetic relationship among Kohanim and their direct lineage from a common ancestor.

Today's Kohanim maintain a number of privileges and obligations within Jewish practice. They recite the Priestly Blessing during some worship services, and they are first to be called up (given an aliyah) to read from the Torah. Kohanim who follow Orthodox Judaism still observe prohibitions such as not marrying a divorced woman or a convert and not visiting a cemetery or coming into contact with the dead.

Question: What is the Priestly Blessing?

Answer: What is the Priestly Blessing?

In the Bible, God commands the Priests (Kohanim) to bless the Children of Israel.

The verses of the Priestly Blessing (Birkat Kohanim) are among the oldest in continuous liturgical use. Archaeologists found the words etched on silver scrolls found in tombs from the seventh century BCE. The words of the Priestly Blessing come from the Book of Numbers 6:24-26.

"May the Lord bless you and keep you.
May the Lord let His face shine upon you and be gracious to you.
May the Lord look kindly upon you and give you peace."

In the time of the Temple in Jerusalem, the Priests recited this blessing every day. Today some synagogues, such as those in Jerusalem, perform this rite every morning. In other synagogues, it is recited only on the Sabbath. In the Diaspora, there are many synagogues that perform this rite only on Jewish holidays, when most of the congregation is gathered.

What special hand gesture accompanies recitation of the Priestly Blessing?

When performing the Priestly Blessing, the Kohanim stretch their arms and hands forward. They hold their hands together palms-down. They split their fingers so there are 5 spaces: one space between the thumbs, a space between the thumb and first finger of each hand, and a space between the second and third finger of each hand.

It is believed that the five spaces allude to verses in Song of Songs (2.8-9). The verses state that God "peeks through the cracks in the wall." In other words, God watches over and protects the Jewish people even when He is hidden.

This hand gesture has been popularized by the Star Trek television series, which used it as the Vulcan ritual of greeting. Use of this gesture on the show was suggested by actor Leonard Nimoy (Mr. Spock), who saw this gesture as a boy in synagogue when he peeked from under his father's prayer shaw (tallit).

When the Kohanim recite their blessing, members of the congregation are supposed to look away. One reason given is that it is easier for the Kohanim to focus on the blessing when the congregation isn't looking directly at them. In addition, it is written in the Talmud (Chagiga 16b), "One's eyes will grow weak if he looks at the hands of the Priests" while they are blessing the congregation.

The symbol of this hand gesture is often engraved on the tombstones of Kohanim. This hand symbol has become symbolic of the Jewish priestly class.