What is the difference between a Mizbe'ach, Bamah and Matzevah?
Gra: A Mizbe'ach is fixed; a Bamah or Matzevah is used haphazardly, on occasions. A Matzevah is from one rock, and a Bamah from many rocks. A Matzevah is only for libations, a Bamah is for Olos, and a Mizbe'ach is for all Korbanos.
Malbim: A Mizbe'ach is fixed, for many to offer on it. A Bamah is for individuals, temporarily. Both of these are from many rocks. A Matzevah is from one rock, and it is only for libations of oil 1 . They set up Matzevos and Asherah trees in front of the Mizbe'ach ? "Lo Sita Lecha Asherah Kol Etz Etzel Mizbach Hashem?; v'Lo Sakim Lecha Matzevah" (Devarim 16:21-22).
Ramban and R. Bechayei (Bereishis 28:18) say that it is also for wine. Yakov poured a Nesech and oil on a Matzevah (Bereishis 35:14)! Perhaps Malbim explains like Ibn Ezra, that the Nesech was to wash it, unlike Targum Yonasan and Radak. Shemos 24:4-5 implies (but does not explicitly say) that each Shevet offered bulls on the Matzevah that Moshe built for it! Perhaps Malbim means that idolaters only poured oil on Matzevos.
Here it says that Asa removed the Bamos. Below (15:17) and in Melachim I, 15:14, it says that the Bamos did not go away!
Refer to Melachim I, 15:14:1:1.
