The Gemara points out that the division of the Shevatim who stood on Har Gerizim and Har Eival resembled no other division in history in which the Shevatim were divided into two groups. Six tribes which descended from Yakov's primary wives (Rachel and Leah) stood upon Har Gerizim, while the four tribes which descended from Bilhah and Zilpah, along with the descendants of Leah's oldest and youngest sons, stood upon Har Eival, as follows: Shimon, Levi, Yehudah, Yisachar, Yosef, and Binyamin stood on Har Gerizim, while Reuven, Gad, Asher, Zevulun, Dan, and Naftali stood on Har Eival.
A careful examination reveals a direct correlation between the order in which the Shevatim were listed at Har Gerizim and Har Eival, and the Berachos and Kelalos which they accepted upon themselves there.
The Torah lists twelve curses to be pronounced during this ceremony (Devarim 27:15-26). The number twelve was chosen presumably because it corresponds to the number of the tribes of Yisrael (Ba'alei ha'Tosfos; Chizkuni). In truth, however, the first eleven curses are summarized by the twelfth, most general, curse: "Cursed be the one who does not accept upon himself to fulfill all of the commandments of the Torah." This curse, however, seems to render all of the preceding, more specific curses extraneous. Rashi (Devarim 27:24) explains that the preceding eleven curses were intended to correspond to eleven of the twelve tribes, while the twelfth curse was directed towards the entire nation. Which tribe was not relegated a curse? Rashi explains that it was the tribe of Shimon. Moshe Rabeinu did not want to direct a curse towards Shimon since he did not intend to direct a blessing towards that tribe before he passed away, as he did with the other tribes.
Rashi apparently means to explain simply why the number eleven was chosen for the number of curses. He does not seem to explain any direct correlation between each of the curses and a specific tribe. The ABARBANEL attempts to link each curse to a specific tribe, although he does so in no particular order. The PIRCHEI NISAN (by the author of KOHELES YITZCHAK) to Parshas Vayishlach suggests that each of the curses corresponds to a tribe in a very clear order; specifically, the order in which the tribes are listed in the section of the Torah which lists the eleven curses (Devarim 27:12-13). With the exception of Shimon, to whom no curse was directed according to Rashi, each of the eleven curses corresponds to a different tribe in the order in which they are listed in these verses. The Pirchei Nisan asserts that this order provides insight into a statement made by the Gemara in Shabbos. The Gemara in Shabbos (55b) states that "whoever says that Reuven sinned is mistaken.... What, then, does the verse mean when it says, 'Reuven slept with Bilhah, his father's concubine' (Bereishis 35:22)? Reuven moved his father's bed out of Bilhah's tent, and the Torah considered it as though he had slept with her." Rebbi Shimon ben Elazar there adds, "The righteous [Reuven] is absolved from sin in this matter. How could it be that Reuven's children would stand upon Har Eival and say, 'Cursed is the one who sleeps with his father's wife,' if Reuven had himself done so?"
Rebbi Shimon ben Elazar proves Reuven's innocence by showing that Reuven's descendants answered "Amen" on Har Eival. Hash-m certainly was not asking them to accept a curse upon themselves. According to the Pirchei Nisan's assertion, however, the Gemara means much more than that.
"Cursed is the one who sleeps with his father's wife" is the sixth curse in the list. Excluding Shimon, Reuven is the sixth tribe mentioned in the list of the tribes which stood upon the two mountains. Rebbi Shimon ben Elazar, therefore, says that the curse for sleeping with the wife of one's father was addressed specifically towards Reuven. Since these curses were part of the establishment of a covenant, Hash-m would not have directed this curse to a tribe which did not fulfill its directive. Rather, Hash-m must have addressed that curse (and its corresponding blessing) towards the tribe of Reuven in order to make it clear that Reuven was free of condemnation for that incestuous act. Their forebear was hence vindicated from suspicion for such a transgression.
The Pirchei Nisan writes further that each of the eleven curses was appropriate to the particular tribe toward which it was directed. Although he explains only the first six of the curses, the TECHELES MORDECHAI (ha'Rav Mordechai Drucker of Strya, Hungary), Parshas Ki Savo, resolves all of them based on the Pirchei Nisan's approach. (The following summary includes some explanations suggested by Rabbis Gedalyah Press and M. KORNFELD. See also Mei ha'Shilo'ach (Izhbitz), vol. II, Parshas Ki Savo.)
The working assumption is that the Torah links a curse to a particular tribe either (a) to show that the sin mentioned in the curse cannot be attributed to that tribe, as mentioned above with regard to Reuven, (b) because that tribe was outstanding in that respect, or (c) because that tribe was more susceptible than the others to sin in such a manner, and thus needed a more direct warning.
1. LEVI. "Cursed is the one who makes idols." The tribe of Levi was the only tribe which did not serve the Egel ha'Zahav (see Rashi to Devarim 33:9). (Pirchei Nisan)
2. YEHUDAH. "Cursed is the one who shows disrespect to his parents." Yehudah promised his father that he would return Binyamin unscathed, and then he risked his life to fulfill his promise for the sake of his father (Bereishis 42:32). (Pirchei Nisan)
3. YISACHAR. "Cursed is the one who tries to take for himself his neighbor's property." Yisachar was conceived when Leah claimed Yakov for herself even though it was Rachel's night. However, she paid Rachel in full for the privilege (Bereishis 30:16). (Pirchei Nisan)
Moreover, Yisachar's leader brought his sacrifices (during the dedication ceremony of the Mishkan) before Reuven's leader. Reuven's leader complained that he rightfully should be first, since his tribal forebear was older, but Hash-m supported Yisachar's leader, saying that it was rightfully Yisachar's turn after all (Rashi to Bamidbar 7:19). (Techeles Mordechai)
4. YOSEF. "Cursed is the one who misleads the blind on the road." When Yosef was on the road trying to locate his brothers, he "blindly" trusted that they would do him no harm. They, however, took advantage of him and harmed him. Thus, he was the only one of the brothers who did not mislead the blind. (Pirchei Nisan)
Alternatively, when Yosef was viceroy of Mitzrayim, his brothers "blindly" stumbled upon him. Although they did not know who he was, Yosef did not take advantage of that fact to take revenge. (M. KORNFELD)
5. BINYAMIN. "Cursed is the one who does injustice to a proselyte, orphan or widow." Binyamin was an orphan, and thus this curse protected him. (Pirchei Nisan)
6. REUVEN. "Cursed is the one who sleeps with his father's wife." As explained above, the Torah addressed this curse to the tribe of Reuven to make it clear beyond any doubt that Reuven was free of condemnation for that sin. Addressing this curse to the descendants of Reuven officially vindicated Reuven from having committed such a transgression. (Pirchei Nisan)
7. GAD. "Cursed is the who cohabits with an animal." The people of Gad gave precedence to their animals even over their own children when they chose their portion of Eretz Yisrael based on where the best grazing grounds are located (Rashi, Bamidbar 32:16). It was therefore necessary to warn them of this transgression more than the other tribes. (M. KORNFELD)
8. ASHER. "Cursed is the one who cohabits with his sister." The women of the tribe of Asher were particularly beautiful (Rashi, Devarim 33:24), and thus Asher needed to be warned of this transgression more than the other tribes. (Techeles Mordechai)
9. ZEVULUN. "Cursed is the one who cohabits with his mother-in-law." The members of the tribe of Zevulun were merchants who sailed long distances to trade their goods with other nations (Rashi, Devarim 33:18). While they were away, their wives would move-in with their mothers so that the women could help each other while their husbands were away at sea. Special warning must be given to the man whose wife and mother-in-law live under the same roof, since a man might become fond of his mother-in-law (Bava Basra 98b; Pesachim 103a). (Rav G. Press)
10. DAN. "Cursed is the one who smites his friend secretly" (who slanders his friend; Rashi). Dan is compared to a "snake" who "bites the hooves of the horses" of his enemy (Bereishis 49:17). He must be warned to direct his destructive energies against the enemy and not to use the character of a snake to slyly hurt others from his own nation. (The Midrash associates the snake with slander. See, for example, Tanchuma, Metzora #2.) (M. KORNFELD)
11. NAFTALI. "Cursed is the one who accepts a bribe to kill the innocent." Naftali was so named because he was born after Rachel used every means at her disposal ("Naftulei... Niftalti") to beg Hash-m to grant her children through her maidservant (Bereishis 30:8). Naftali, therefore, had a tendency to attempt to attain his will through any means, however illicit, and thus he in particular needed to be warned not to be involved with bribes. (Rav G. Press)