שָׁ֤ם בִּנְיָמִ֨ן ׀ צָעִ֡יר רֹדֵ֗ם שָׂרֵ֣י יְ֭הוּדָה רִגְמָתָ֑ם שָׂרֵ֥י זְ֝בֻל֗וּן שָׂרֵ֥י נַפְתָּלִֽי׃
Naroon si Benjamin, ang pinakabata, na namumuno sa kanila; ang mga pinuno ng Juda ay bumato sa kanila, gayundin ang mga pinuno ng Zabulon at ang mga pinuno ng Neftali.
Rashi
Judah became His holy nation He took Judah as the lot of His portion and His sanctity, and even they sanctified His name when they descended into the sea, as the matter that is stated (above 68: 28): “the princes of Judah pelt them with stones.” Similarly, this verse is explained in the Aggadah (Mid. Ps. 114:8): Judah became His holy people, for Nahshon sprang into the sea and said, “I shall descend first,” and that is what [the Psalmist] says: Judah became His holy people.
Rabbeinu Bahya
A kabbalistic approach: The word אלי in this verse is equivalent to the word לי which we find in connection with Terumah, the gift intended for G’d, i.e. the donations for the Tabernacle. We read in the ספר הבהיר of Rabbi Nechunyah ben Hakanah (item 103 edition of Margulies) that the words ויקחו לי תרומה should be understood as ויקחו ל-י תרומה, “they are to take a gift intended for the י.” The idea is that every prayer must be addressed exclusively to the י, to Hashem. It is in this sense that G’d said to Moses: ”speak to the Children of Israel ויסעו they are to journey from below to above and the sea will part as a result.” They were to call on their reserves of faith and elevate themselves to the level י. Whereas the address for their attention was G’d in His capacity as the attribute of Mercy, the attribute they wanted Him to activate was His attribute of Justice. Moses did as G’d said and informed them of the great miracle which was about to occur whereupon the Israelites started marching forward.
In Sotah 37 we are told that the tribe of Yehudah sanctified the name of the Lord by being the first one to enter the sea. Midrash Tehillim 114 on the words היתה יהודה לקדשו, “Yehudah became His holy one,” deduces this from these words of the psalmist. This is also what is meant by the words: “the sea saw and fled” (Psalms 114,3). What did the sea see? It observed Nachshon ben Aminadav, the prince of the tribe of Yehudah, enter it, followed by the other tribes who drew encouragement from Nachshon’s behaviour. In fact, they now each wanted to be first to wade through the bed of the sea. According to Psalms 68,28: “there is little Binyamin who rules them.” The word רדם in this verse which means “rules them,” should be read as two words, i.e. רד ים, “descended into the sea.” According to that tradition the brother tribes Yehudah, Naftali, and Zevulun stoned the Binyaminites for having arrogated to themselves the right to be the first ones to enter the sea. This is based on Psalms 68,28 where the Midrash understands the word רגמתם, as “they stoned them.” The Midrash claims that the reason that the prince of Yehudah was called נחשון, was in recognition of his pre-empting the other Israelites in descending into the sea, i.e. he was a נחשול, “a gale smiting the sea.”
In Sotah 37 we are told that the tribe of Yehudah sanctified the name of the Lord by being the first one to enter the sea. Midrash Tehillim 114 on the words היתה יהודה לקדשו, “Yehudah became His holy one,” deduces this from these words of the psalmist. This is also what is meant by the words: “the sea saw and fled” (Psalms 114,3). What did the sea see? It observed Nachshon ben Aminadav, the prince of the tribe of Yehudah, enter it, followed by the other tribes who drew encouragement from Nachshon’s behaviour. In fact, they now each wanted to be first to wade through the bed of the sea. According to Psalms 68,28: “there is little Binyamin who rules them.” The word רדם in this verse which means “rules them,” should be read as two words, i.e. רד ים, “descended into the sea.” According to that tradition the brother tribes Yehudah, Naftali, and Zevulun stoned the Binyaminites for having arrogated to themselves the right to be the first ones to enter the sea. This is based on Psalms 68,28 where the Midrash understands the word רגמתם, as “they stoned them.” The Midrash claims that the reason that the prince of Yehudah was called נחשון, was in recognition of his pre-empting the other Israelites in descending into the sea, i.e. he was a נחשול, “a gale smiting the sea.”
Rashi
You are the head of the tribes of Yisroel. Targum Yonoson renders, 'the tribe of Binyomin crossed the [Reed] Sea ahead of all the people, as it is said, 'Binyomin, the youngest, rules them.'18Tehillim 68:28. You did not follow in Binyomin’s tradition of taking charge and leading the people without questioning the command of ‘ה. You have thus forfeited the merit by which you became king.