Saying good-bye is never an easy task. What parting words do we hope will linger in the air after we have departed for a new destination? What leave-taking blessing should be uttered until we meet again? Our sages tell us that people should not part ways amid chatter, nor on a note of laughter, lightheadedness or idle words. Saying good-bye is a key moment and the parting talk should be the language of Halacha (B. Berachot 31a). To buttress this contention, the Talmud cites the practice of the prophets, who while being divinely moved to warn the people of impending punishments, concluded their message with words of hope and comfort. To cite a clear example: The first 13 chapters of Hosea contain prophecies of doom, and the theme of the book appears to be a harsh critique of Israel. Yet the concluding chapter departs from this topic, promising that God and Israel will eventually be reconciled. Parting words need to be carefully considered as they leave a lasting impression; the final note before taking leave should be spiritually uplifting, not stark prophecies and certainly not inane babble. The Talmud continues citing a similar ancient tradition that adds an explanation of the significance of parting with words of Halacha: "For this way he will remember him." Who is remembering whom in this passage? One option is to suggest that God recalls the parting friends. Earlier in our tractate, our sages discuss God's presence in various holy undertakings (B. Berachot 6a). Quoting the biblical verse "then those who fear God spoke to one another, and God listened" (Malachi 3:16), our sages tell us that when two people study Torah together the divine presence is with them. Furthermore, the Almighty is not only at hand when two people study Torah, but is present even when an individual sits alone and studies Torah. This is indicated by God's assurance: "Wherever I permit My name to be mentioned, there I will come to you and bless you" (Exodus 20:21). The Talmud asks the obvious question: Since God is present when an individual learns Torah, surely the divine presence rests on two people who study? Explaining this anomaly, the Talmud suggests a difference between the divine presence at a lone study session and God's company when two people learn: When an individual studies Torah, indeed the Almighty is present; when two people learn Torah, not only is God present but the words of their study session are recorded in a book of remembrance. Thus the words of Torah of friends parting are recorded before the Almighty, and it is God who remembers the parties and their Torah interaction long after they have parted ways. While this approach elegantly invites God into the interaction between two friends, the passage does not seem to be referring to the Almighty's presence. A more likely interpretation has the friends remembering one another after they have said good-bye. Why by offering parting words of Halacha do we improve the chances of remembering friends? Perhaps this mechanism works because of another rabbinic directive. Our sages tell us that citing Torah sources brings redemption to the world (M. Avot 6:6 and parallels). They add that not citing sources is a cause of bringing a curse on the world. In one place, they go further, suggesting that people who refrain from mentioning sources effectively kill, as they act as if the person from who they received the teaching does not exist. Moreover, the Talmud tells that people who say halachic matters in the name of the original source, should imagine the person who authored the teaching standing before them as they share the teaching (Y. Kiddushin 61a). With this encouragement to cite sources and with a vision of the author present when the Halacha is being taught, it is clear why parting on matters of Torah assists memory. In an inspiring autobiographical passage, Zalman Shazar (1889-1974) told of his last Shabbat with his grandfather in the Byelorussian town of Mir, before the young idealist made the journey to Palestine. Shazar grew up in an ardently Lubavitch hassidic family. At a young age he was drawn to Zionism, and his student days were filled with Zionist activism. After the establishment of the State of Israel, Shazar served as the first minister of education and culture in 1949 and his tenure in that position is commemorated today on the NIS 200 bill. In 1963, he became the third president of Israel. In 1924, Shazar - or Shneur Zalman Rubashov as he was then known - began the journey to Palestine. On his route toward the Promised Land, he spent a nostalgic Shabbat with his grandfather. As the time to part arrived, grandfather and grandson made their way out of the town. As they walked together, the old man spoke of the unique value of a melody connected to the soul of the singer. As Lubavitcher Hassidim, explained the grandfather, the souls of the Rubashov family were tied to the melody of the Old Rav, Rabbi Shneur Zalman of Lyady (1745-1812). When the two were about to part, the old man followed the talmudic directive, posing a complicated legal problem and offering a solution. The warm memory of that parting from his grandfather stayed with Shazar for the rest of his life, but not because of the Halacha discussed as the waggoner urged his passenger to board; the details of that lesson remained sketchy in the mind of Shazar. Instead, Shazar took with him the parting melody that his grandfather had lauded: "In all the perplexities of my life, whenever I have suddenly wished to remember the melody of the Old Rav and the good tune has responded, I have felt new strength welling up within me each time, evidence that my direction is right. All despair conquered, I have gone my way in hope and inner peace." 'Our sages guide us to the words of Torah, to leave an indelible mark and a lasting impression The writer is on the faculty of Pardes Institute of Jewish Studies and is a rabbi in Tzur Hadassah.