3,835. The Dimensions of the Altar

Hilchos Beis HaBechirah 2:3

The dimensions of the altar are very specific and were transmitted by tradition from generation to generation. The altar built by the exiled Jews who returned from Babylonia was built based on the specifications for the future altar. No alterations may be made to the dimensions of the altar.

Hilchos Beis HaBechirah 2:4

Three prophets (namely Chaggai, Zechariah and Malachi) returned to Israel with the Babylonia exiles; one of them testified as to the location of the altar, the second testified as to its dimensions, and the third testified that all sacrifices could be offered on that altar even though the Temple was not yet built.