Jewish Festivals, Rituals, Practices. Jewish Festivals. Nature is the key (not clocks and calendars) days begin at nightfall lunar month: 29 1/2 days solar year (365 1/4 days) festivals follow seasons. Jewish Calendar. NameMonthLength Gregorian of MonthNumberof MonthEquivalent
Jewish Festivals, Rituals, Practices
of MonthNumberof MonthEquivalent
Cheshvan829 or 30 daysOctober-November
Kislev929 or 30 daysNovember-December
Adar1229 or 30 days February-March
Adar II1329 daysMarch-April
Source: Norman Solomon, Judaism.