While traveling through the desert, the Children of Israel were commanded to build a collapsible Tabernacle complete with implements for sacrifice. Upon entering the Land of Israel they were commanded to build a Temple — a permanent structure where sacrifices would be brought — although this mitzvah was not fulfilled until the time of King Solomon, hundreds of years after the land was settled. During the interim, the altar was set up on a semi-permanent basis in places like Shilo, Nov and Giv’on.
According to Sefer Yehoshua (18:1), the first established resting place for the Tabernacle was Shilo, where it stood until the war with the Pelishtim during the time of Eli the High Priest, as described in Sefer Shmuel (I, Chapter 4). As theMishnah explains (Zevahim 112b), this was a permanent structure made with a stone foundation and the Tabernacle coverings as a roof. Following the destruction of the Tabernacle in Shilo, its remains were erected in Nov, as we learn from the story during King Sha’ul’s reign (see I Shmuel 21:7), and later we find that King Solomon sacrificed at the great altar in Giv’on (see I, or Kings 3:4).
Rav Huna quotes Rav as teaching that when the altar was established in Shilo, it was constructed of stones, quoting abaraita where we find Rabbi Eliezer ben Ya’akov teaching that the word avanim — stones — appears three times, once inSefer Shemot (20:21), and twice in Sefer (27:5, 6), to teach that the altar must be built out of stones in Shilo, in Nov and Givon, and in the permanent Temple.
A number of explanations are offered for this teaching. Rabbi Natan, for example, understands that the altar in Shilo was the original hollow copper altar from the Tabernacle, but that it was filled with stones. Rav Papa suggests that there were two altars — the original copper one and the new stone altar — both of which received Heavenly fire at different times.