Parshat Reeh talks about the prohibition of bringing sacrifices anywhere outside of the Beit Hamikdash once it is erected. Perek 12 Pesukim 5-6 of Reeh state: “Ki Im El Hamakom Asher Yivchar Hashem Elokeichem…Vehaveitem Shama Oloteichem [עלתיכם], “Rather, only to the place that Hashem, your G-d will choose…you will bring your burnt offerings.” In the same Perek, Pasuk 12, the Torah writes “Vehaya Bamakom Asher Yivchar Hashem Elokeichem Bo Lishaken Shemo Sham Shama Taveu… Oloteichem [עלותיכם],” meaning, “It shall be that the place where Hashem, your G-d, will choose to rest His Name- there you shall bring…your burnt offerings.”
The obvious question arises- if the Torah does not use extra phrases, why is this commandment written twice? Rashi explains that the first commandment is talking about the prohibition of building a personal Alter in the time of the Mishkan in Shiloh and the second commandment is the prohibition of building a personal Alter during the time of the Beit Hamikdash. However, another issue arises. Why is the first Oloteichem written Chaser, missing a Vav, while the second Oloteichem is written Maleh, with the Vav?
Rav Moshe Feinstein, in his Sefer Darash Moshe, says that we find in the book of Shoftim that in the times of the Shoftim (Judges), Bnai Yisrael served Hashem appropriately. However, between each Shofet (Judge) there is a time when Bnai Yisrael sinned and turned away from Hashem, subsequently resulting in the appointment of a new Shofet. It is for this reason that the Beit Hamikdash was not built during their time, rather the Mishkan. Yet even though they had the Mishkan it was still not complete like the Beit Hamikdash, so the text is written Chaser. Conversely, when the Beit Hamikdash was built in the time of Shlomo, the ability of Bnai Yisrael to worship Hashem was complete, and that is why the text is written Maleh.