Hillel II Calendar
The Modern day Jewish and Israeli calendar that dates from the time of Hillel II (359 C.E.). It is a lunisolar calendar based on computations rather than visual observations. Due to a slight miscalculation the start of the Hebrew year is occurring later and later each year. Relative to the Gregorian calendar, the Jewish calendar is creeping one-day every 237 years. This error means the calendar could be late by an estimated 25 days.

| Start of the 7 main Feasts.
| Represent the other days of the 7 main Feasts.
| Start of the 2 Feasts that were added later.
| Represent the other days of the 2 later Feasts.
| Events.

| 49 days leading up to Pentecost (50 days) from Passover.
| 1st 40 days Moses spent obtaining the law.
| 2nd 40 days Moses spent pleading with God.
| 3rd 40 days of Moses when he receives the law again.

Months
The months of the calendar follow the cycle of the moon. Each month starts on the new moon, the middle of the month is a full moon and ends with no moon. Twelve standard months make up the year, and an extra month Adar 2 is added on leap years. These leap months are added to keep the year lined up with seasons. This type of system is called a Luna-solar calendar. Each month has either 29 or 30 days.

Days
Each day ends after sunset, not at midnight like we expect today. So the Passover meal is Celebrated on the 15th Nisan according to the Jews, but by Western standards on the evening of the 14th after dark.

Pattern of the Leap Years
The modern Hebrew calendar follows a 19-year rotation called the Metonic cycle. Years 3, 6, 8, 11, 14, 17, and 19 of the Metonic cycle are leap years. 3761 BCE is calculated by the Jews as Year 1. While this is year 1 by Jewish estimates others believe we are missing over 200 years.

Year Beginnings
The civil year ends on the month of Adar (or Adar 2 on leap years) and begins on the feast of trumpets Tishrei 1, during the autumn. This is the traditional year's start and end but after the Passover, we are told to change the start of the year on Nisan 1.

Exodus 12:2
"This month shall be for you the beginning of months. It shall be the first month of the year for you."

Nisan the first month in spring and occurs 6 months earlier than the Jewish New Year. While this is confusing our Gregorian calendar has similar quirks. The new year happens on the 1st of January, the school year starts in September, and the tax year ends in April. The Hebrew year follows its 7 Feast commanded in Leviticus 23 following the harvest from the first fruits of barely till the final reaping of the grapes.

Festivals
The seven feasts are found in Leviticus 23. 4 feasts occur in the spring, and 3 feasts in the autumn.

Spring Feasts	Event	Date
Passover	They eat the Passover meal, and spread the blood on their door posts, in remembrance of the exodus. Either Last Supper or Cruxifician Day.	Nissan 15 or Iyar 15
Unleavened Bread	They eat unleavened bread for 7 days, to remind them of the haste they left Egypt. Symbolises Jesus dead and buried.	Nissan 15-22
First Fruits	Beginning of the harvest season. where the Israelites would bring the first sheaf of their barley harvest to the priest as an offering to God. Jesus Raised from the dead.	First day after the Sabbath following Passover.
Pentecost / Law Given / Offering	Wheat harvest offering. Law given to Moses, and Holy Spirit given to Christians.	Sivan 6, 50 days after Passover.

After Pentecost, we have 120 days indicated in blue, green and purple running over the feast of trumpets to the Day of Atonement. These 120 days are the days it takes Moses to receive the law from God.

|40 days - Pentecost to the Goldern Calf idolatry.
|40 days - Moses pleading with God for the idolatry.
|40 days - To go up Mount Sinai to receive the law afresh.

Autumn Feasts	Event	Date
Feast of Trumpets	Beginning of the Civil Year, The sound of the trumpet serves as a call to repentance, in the run-up to the Day of Atonement. Called the hidden day because its based on the siting of the moon.	Tishrei 1 or 2
Day of Atonement	On this day, the high priest would enter the Holy of Holies in the Temple to offer sacrifices and sprinkle the blood of the atonement sacrifices to purify and reconcile the people with God.	Tishrei 10
Feast of Tabernacles	Celebrated for 7 days, the Israelites have to make shelters reminding them of the 40 years in the wilderness.	Tishrei 17 - 23

Later Feasts
Over time 2 more feasts were added to the Calendar.

Extra Feasts	Event	Date
Purin	Feast dating from the time of Esther about 450 BCE. The Jews successfully fought back and defeated their adversaries, ensuring their survival.	Adar 14-15
Hanukkah	To celebrate the rededication of the 2nd Temple, dated 165BCE.	25 Kislev (for 8 days)