שָׁל֣וֹשׁ פְּעָמִ֣ים ׀ בַּשָּׁנָ֡ה יֵרָאֶ֨ה כָל־זְכוּרְךָ֜ אֶת־פְּנֵ֣י ׀ יְהוָ֣ה אֱלֹהֶ֗יךָ בַּמָּקוֹם֙ אֲשֶׁ֣ר יִבְחָ֔ר בְּחַ֧ג הַמַּצּ֛וֹת וּבְחַ֥ג הַשָּׁבֻע֖וֹת וּבְחַ֣ג הַסֻּכּ֑וֹת וְלֹ֧א יֵרָאֶ֛ה אֶת־פְּנֵ֥י יְהוָ֖ה רֵיקָֽם׃
你所有的男丁一年三次要在永恆者你的上帝所選擇的地方朝見祂，就是在無酵節、七七節和住棚節；他們不可空手朝見永恆者。
Rashi
ולא יראה את פני ה׳ ריקם AND THEY SHALL NOT APPEAR BEFORE THE LORD EMPTY, but — bring the burnt offerings that are obligatory when one appears before the Lord, and the peace offerings of the festival.
Ibn Ezra
one must not appear… and consequently, one must bring the abovementioned “tribute of a freewill offering of your arm” [: 10].
Chizkuni
שלש פעמים בשנה, “three times annually;” why did this have to be repeated? In order that you should not say that seeing that when the Torah writes about the festival of Shavuot in verse 11: “you shall rejoice in the presence of the Lord your G-d, you, your son and your daughter, your male servant as well as your female servant;” whereas on the Passover festival when no mention has been made of joy, the father need not take along his family, and the Torah had spoken of “all your males,” the sons have to be taken along on each of these festivals. A different interpretation: the instruction had to be repeated as we might have thought that the commandment not to appear before G-d emptyhanded which is written only here and in connection with Passover, also applies on the third pilgrimage festival.