Before the advent of a common calendar, people reckoned the “dates” by natural observations.

Months are determined by the cycle of the moon.
From new moon to new moon is a month.

Days are determined by the cycle of the sun.
From sunset to sunset is a day.

Seasons are determined by the cycle of the crops.
Ripening grains signals spring.

According to God’s instructions in the Bible, Passover (Pesach) begins at sunset the eve of the fourteenth day following the first full moon (in Israel) after the grain begins to ripen in Israel.

This year, according to two or more witnesses in Israel, it begins at sunset Sunday, April 1, 2018. It is a Sabbath with the God of Israel and those who follow the God of Israel.

This date also marks the beginning of the observance of the week of Unleavened Bread during which no leavened bread is to be eaten.
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