First Visible Crescent or Unseen Conjunction Moon: Which should start the month?

Question: Recently, there are people who share the Sabbath of the lunar calendar together. There is a debate among them on the crescent observation section as a way to keep the lunar calendar. One group is arguing with the app provided by the WLC and the other with the app provided by Israel. The point of people using the Israeli app is that the WLC-provided app also captures the moon's phases that cannot be observed with the naked eye in observing the moon before the start of the lunar calendar. For example, when observing the lunar phase, it is argued that a phase of less than 0.8% is a phase of the moon that cannot be recognized as pre-moon. I want to know exactly which one is right. Please help me.

Answer: WLC once believed that the first visible crescent was the beacon for beginning the Biblical month. After much study, though, WLC became convinced that New Moon Day is to be reckoned by the lunar-solar conjunction.

Problems with Using the First Visible Crescent:

• Using the first visible crescent method, it is impossible for the world to consistently begin the Feasts during the same 24-hour period (which results in multiple New Moon Days and Sabbath Days). The only way to remedy this, when using the crescent moon, is to use the man-made International Date Line.
• Not consistent with the principles governing the Biblical parameters of a day
• Chodesh, the Hebrew word for "New Moon," is used in Scripture more than 270 times, yet it is not used even once to denote seeing something (i.e. the visible moon, the crescent, ...). The Hebrew word for "crescent," śaharōnîm, is used exclusively in connection to idolatry.
• Not in harmony with Psalm 81:3
• Not in harmony with Genesis 1
• Not in harmony with Nature's (Creation's) testimony
• Not in harmony with the Writings of Philo, a contemporary of our Saviour (20 B.C.–50 A.D.)

More details on the above points are provided here: New Moon Day: The Dawn After Conjunction

For more on this important topic, kindly refer to the following:

• The Creator’s Calendar (Content Directory)
• Calculating the Conjunction: No Computer? No Problem!
• Future Lunar-Solar Conjunction Dates (2013-2030)