Q.   I notice you do not use the secular calendar when setting up the Annual Holy Days. Why do you not follow the present Jewish calendar rather than determine probable visual sightings of the new moon, and then expect people to go look for it?

A.  The world calendar is a solar calendar, based upon the 365 ¼ days it takes the earth to make a complete revolution around the sun (solar year).  The lunar year is 354 ½ days, or 11 days shorter. 
            Although etymologically based on the word moon, the months (“moonths”) of the worldly calendar do not follow the waning and waxing of the moon at all.  The thin new moon appears every 29 or 30 days, and the first visible sighting of this rebuilding phase is known as the “new moon” day or the beginning of the month.
            Our present Gregorian calendar ignores new moons, and divides the year into 12 periods, calling them months.  Its days begin at midnight, but scripturally days begin and end with sunset.  The calendar in the Bible is based upon the circles of the moon about the earth, adjusted seasonally by the earth’s movement about the sun.
            The Biblical calendar begins in the spring, near the time of the vernal equinox, and is based upon an area of Jerusalem where green heads of barley will be available at the time of the Passover season.  This was the custom during the time of the Messiah with empirical sightings of the new moon.
            After the destruction of the Temple the Sanhedrin could no longer meet to verify new moon sightings and sanctify the new month.  In the year 359 C.E. Hillel II published the present calculated Jewish calendar.
            We do not use the present Jewish Calendar for several reasons.  They begin their year in the fall in the seventh month of Tishri instead of spring.  Yahweh clearly tell us in Exodus 12:2 of the spring month of Abib, “This month (moon) shall be unto you the beginning of months; it shall be the first month of the year to you.”
            The present Jewish calendar has a series of dehioth (postponements rules) that are nowhere found in the Bible.  For example, the day of Atonement cannot precede or follow the weekly Sabbath.   Also, Trumpets shall not occur on a Sabbath.  Passover as well can fall only on Monday, Wednesday, Friday or Sabbath.
            Arthur Spier’s book, The Comprehensive Hebrew Calendar, makes this note in explaining the postponements: “In more than 60 percent of all years Rosh Hashanah [Trumpets] does not occur on any of the Molad [conjuction] but is postponed according to one of the Dehioth.  Therefore the Dehioth [postponements] are actually not the exceptions to the rule but the rule.”  Yahweh did not give this calendar to Moses, and there is no record that it was used in Yahshua’s time.
            Moon spotters would search the western skies at sunset every 29 or 30 days seeking the thin crescent just above the horizon.  The Sanhedrin would verify the new moon day upon examination of the witnesses by the blowing of trumpets.
            Furthermore, should a follower of Yahshua be isolated and not have access to fellowship, he would still be responsible for keeping Yahweh’s Holy Days and would be able to determine for himself if required.
            We strive to keep the Feast Days as given in the Bible and kept by the Savior.  The Jewish Calendar was revealed to the world in the 4th century and is a masterpiece of mathematical and astronomical calculation.  However, it is the work of man.  Having the year begin in the fall at Trumpets and postponing various Feast Days is nowhere sanctioned by the Bible.