Where does the halacha for kiddush levana (blessing for the New Moon) come from and have there been any Torah authorities who were opposed to it?
Dear Peter Merker,
The source for blessing the new moon comes from the Talmud. To my knowledge, there have never been any Torah authorities who opposed it.
I assume that your question is based on the misconception that sanctifying the moon bears a resemblance to moon-worship. This is an absolute fallacy. We are not worshipping the moon, we are praising G-d for His marvelous creations, including the miracle of the moon's monthly rebirth. One of the principal ways to recognize G-d is through G-d's works; the immutable monthly cycle of the moon is one of the more visible aspects of G-d's masterful creation.
Additionally, we see the monthly rebirth of the moon as a symbol of G-d's promise to ultimately redeem the Jewish People and to make us whole again.
- Talmud Sanhedrin 42a