In the lead-up to the plague of locust, G-d tells Moses, “Bo el Pharaoh – Come to Pharaoh” (Exodus 10:1). Many commentators are troubled by this strange verbiage as one would have otherwise expected G-d to say, “Lech el Pharaoh – Go to Pharaoh,” which is what He says to Moses in telling him to warn Pharaoh about the plague of blood (ibid. 7:15).
The Baal HaTurim (to Exodus 10:1) writes that “bo” has a gematria of three, which alludes to the fact that three more plagues were left at that point until the Exodus. Rabbi Menachem Mendel Kasher (1895-1983), however, notes that Hashem uses the word “bo” instead of “lech” two other times when telling Moses to meet Pharaoh (ibid., 7:26 and 9:1), and at neither of those points were three plagues remaining.
The Baal HaTurim and other Tosafists (see Hadar Zekanim to Exodus 9:1 and Moshav Zekanim to Exodus 10:1) point out that when G-d tells Moses to meet Pharaoh in the latter’s house, He says, “Bo el Pharaoh,” but when He tells Moses to meet Pharaoh at the river, He says, “Lech el Pharaoh.” Apparently, then, “bo” means specifically entering a building, while “lech” means generally going somewhere (see also Ramban to Exodus 8:15).
The Zohar interestingly seems to echo this idea (Bo 34a), stating that “Bo el Pharaoh” teaches us that G-d brought Moses into some sort of heavenly inner chamber that was somehow associated with the sea-creature that characterizes Egypt.
Rabbi Elimelech of Lizhensk (1717-1786) offers two more differences between “Bo el Pharaoh” and “Lech el Pharaoh”: 1) “bo” implies repeatedly going to Pharaoh, while “lech” implies going once; and 2) “bo” implies willingly going to Pharaoh, while “lech” carries no such implication.
As an English speaker, I am tempted to say that “bo” focuses on one’s destination (come to), while “lech” focuses on one’s place of departure (go from).
The Hebrew verb “l’havi” (to bring) is actually a conjugation of “bo,” as bringing something from one place to another essentially causes that item to go from one place to another. Accordingly, Rabbi Yaakov Tzvi Mecklenburg (1785-1865) suggests reading “Bo el Pharaoh” as “Bring the following message to Pharaoh.”
Rabbi Shlomo Pappenheim of Breslau (1740-1814) writes that “navi” (prophet) is derived from the root bet-aleph because prophets bring G-d’s words to people. Rabbi Pappenheim further explains that the type of coming denoted by “biah” can be either reaching one’s destination (I came home) or journeying towards one’s destination (I am coming home).
Rabbi Pappenheim and Rabbi Aharon Marcus (1843-1916) trace the root of “bo”/“biah” to the monoliteral root bet, which means inside since when a person comes to a certain place, he goes inside it.
Rabbi Samson Raphael Hirsch (1808-1888) connects “bo” with the phonetically similar “po” (invoking the interchangeability of bet and peh), explaining that “bo” focuses on one’s final destination just as “po” (here) focuses on one’s present location. He even adds that “peh” (mouth) is related to these words because the mouth is the final terminus into which food goes.
Another Biblical word for coming is “attah” (e.g., Deuteronomy 33:2 and Isaiah 21:12). According to Rabbi Pappenheim, “attah” implies a more final coming, exclusively referring to arriving at one’s destination and never the journey getting there.
He maintains that “attah” is derived from the monoliteral root tav, which represents the notion of bordering since it bookends the Hebrew alphabet as the last letter. A border is a sort of invisible line that connects two bodies but also distinguishes between them. Thus, words derived from this one-letter root are related to bordering and connecting.
For example, “et” functions as a grammatical sign that connects a verb to its object and sometimes bears the meaning of “with,” and “oht” (sign) forms a semiotic connection between the sign and the signified. In the same way, “attah” can be understood in the sense of connecting the traveler with his destination. (Perhaps the finality and closure of “attah” is hinted at in its root, which contains the first and last letters of the Hebrew alphabet, while “biah” only contains the first letter.)
Interestingly, the word “tav” (sign or mark) derives from the monoliteral root tav because a tav serves as a sort of border that distinguishes something from everything else. In fact, the prophet Ezekiel relates that he saw G-d command an angel to make a mark (“tav”) on the foreheads of the righteous men who bemoaned the abominations that took place in Jerusalem, and the Talmud (Shabbos 55a) explains that the mark was a letter tav.
Similarly, the Bible (Gen. 4:15) reports that G-d promised to protect Cain in exile by giving him an oht (sign or letter), which some explain was the letter tav.
What’s even more fascinating is that in the original ivri script of Hebrew, the letter tav was written in the same shape as the English letter x. Thus, just as X serves as a symbol – marking the spot or standing for a word or number that’s missing (e.g., in algebra, x appears as an unknown variable) – tav serves as a symbol marking something as distinguished.