There is a reference in Parshat Re’eh to two important terms in Judaism. One is called היתר במות and the other is הוראת שעה. This is connected to the location where sacrifices may be offered.
The term Heter Bamot, refers to a brief period in our history when the Mishkan and Beit Hamikdash were not in operation.
From the time the Jewish people entered Eretz Yisrael, the Jewish people worshipped Hashem either in the Mishkan or in the Beit Hamikdash. The Mishkan was referred to as a portable Temple, that was originally built in the desert. In Israel, it was in Nov and Givon, for a certain period, and mainly in Shilo, for 369 of the 480 years, before Solomon’s Temple was built.
The Heter Bamot applied during the brief interim period, where both the Mishkan and the Beit Hamikdash were not functioning. Only then, was it permitted to build private altars where free will offerings could be offered.
The Hora’at Sha’ah is the situation where permission is granted to a prophet to violate the Torah for the sake of saving the Jewish people. This happened once in the days of Eliyahu Hanavi, when he had a confrontation with the false prophets of Baal. Jewish survival was at stake, and he used this special, emergency leniency, to offer a sacrifice on Mount Carmel. He needed to show the truth of Hashem’s Torah, by having a fire come from the sky and consume his sacrifice.
The reference to these two terms of היתר במות and הוראת שעה, was to emphasize the importance of having one central place of worship for the Jewish people. We know what happens when there is a splintering of our people, and each does what is “right in his own eyes.” Jewish Unity is essential for the strength and success of Israel.