Halakhah do Liczb 8:4

During the entire month of Nisan we do not say Tachanun¹See Chapter 22. or Tzidduk Hadin²See Chapter 198:14. (burial service), and we do not say Tzidkasecha on Shabbos at Minchah.³Shulchan Aruch 429. It is customary⁴This custom is not very widespread in our times, except among Chassidim. from Rosh Chodesh on, to read (from the Seifer Torah) the parashah of the Nasi⁵The leader of each tribe was called Nasi. On Rosh Chodesh Nisan the Tabernacle was erected, and in honor of its dedication, during the ensuing twelve days, each Nasi had his day on which he brought a special offering, as is written in Numbers 7:10–7:89. who brought his offering on that day. On the thirteenth day of the month, we read in parashas Beha'alosechah until "Kein asah es hamenorah" "So did he make the Menorah" which is fitting for the tribe of Levi.⁶Aaron, the High Priest, and Nasi of the tribe of Levi did not take part in the offering of the Nesi’im. His lighting of the Menorah was his part in the dedication. See Rashi. (Numbers 8:2)

Each day [of Chanukah] we call up three men [for the reading of the Torah] from the chapter "The Offerings of the Princes" in the weekly portion of Naso. On the first day we begin to read for the kohein, from Vayehi beyom kalos Moshe, [On the day that Moses completed] (Numbers 7:1) until Lachanukas hamizbei'ach, [For the dedication of the altar]; for the Levi, Vayehi hamakriv bayom harishon, [The one to bring his offering on the first day] etc. until melei'ah ketores [Filled with incense]. For the Yisrael, Par echad, [One young bull] etc., until Ben Aminadav. On the second day for the kohein and the Levi, we read, Bayom hasheini [On the second day] etc., and for the Yisrael, Bayom hashelishi, [On the third day] etc. Similarly, on each subsequent day for the kohein and the Levi we read of the current day's offering, and for the Yisrael, the offering of the next day. On the eighth day, for the kohein and the Levi, we read, Bayom hashemini [On the eighth day] etc., and for the Yisrael we begin with Bayom hatesh'i, [On the ninth day], completing the entire parashah, and we continue in parashas Beha'alosecha, until kein asa es hamenorah, [So did he make the menorah] (Numbers 8:4).