The Mishnah was the first recording of the oral law written by the Scribes and Pharisees between 70-200 CE, that is about 37 to 167 years after the Messiah's death. The Mishnah explains that the New Moon Day was determined by the observance of the Crescent New Moon. It was the general understanding that New Moon meant Crescent New Moon Day. The Crescent New Moon Day begins the count to all the Holy Days and the Messiah kept the New Moon Feasts and the Annual Feasts as Holy Days, thereby proving that they are the "True Appointed Times of God," based on the observance of the Crescent New Moon. The Mishnah also explains how the Beth Din (Sanhedrin Court) would examine the witnesses who observed the Crescent New Moon, to see if the witnesses testimonies were true. It clearly shows that the witnesses were observing the sky to see the first appearance of the Crescent New Moon that appears after the conjunction:
MISHNAH - ROSH HASHANA 2:6 (Page 190) says:
"How were the witnesses examined? The first pair were examined first. The elder was introduced first, and they said to him: Tell us in what form thou sawest the moon; was it before or behind the sun? Was it to the north or the south (of the sun)? What was its elevation on the horizon? Towards which side was its inclination? What was the width of its disk? If he answered before the sun, his evidence was worthless. After this they introduced the younger (witness) and he was examined; if their testimony was found to agree, it was accepted as valid; the remaining pairs (of witnesses) were asked leading questions, not because their testimony was necessary, but only to prevent them departing, disappointed, and to induce them to come again often."
Rabban Gamaliel had on a tablet, and on a wall of his upper room, illustrations of the various phases of the moon, which he used to show to the common people, saying: "Did you see the moon like this figure or like this?"
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