The original Sabbath was Saturday before it was moved to Sunday by Constantine on the 7th of March 321 AD. Originally Sunday was used by pagan Rome to celebrate the sun god.
Jesus was born 20 March 6 BC or 1 Nissan 3756, the first Christmas was celebrated on the 25th of December 336 AD, A few years later, Pope Julius I officially declared that the birth of Jesus would be celebrated on the 25th December. Originally pagan roman would light fires during this time to help the sun god to gain power over winter.
Jesus enters Jerusalem
11th of Nisan 3790 or 31 March 30 AD
Jesus has his last Passover meal. He gave his disciples unleavened bread as his body to eat and wine as his blood to drink.
14 Nissan 3790 or 3de of April 30 AD (Passover evening)
Day of crucifixion
Jesus died for our sins on 15 Nissan 3790 or 4th of April 30 AD (Passover)
Day of resurrection
Jesus awoke from death on 18 Nissan 3790 or the 7th of April 30 AD
Day of ascension
On the 17th of May 30 AD or 28 Iyar 3790 Jesus ascended to heaven; to be seated at the right hand of God and to prepare a place for us in Heaven.
Day of Pentecost
On the 27th of May 30 AD or Sivan 9 3790 the Holy ghost came to earth in the form of fire and dwelt with us ever since.
Just for interest sake
13 September 30 AD Rosh Hashana Feast of Trumpets
22 September 31 AD Yom Kippur Day of Atonement
6 December 31 AD Chanukah Re-dedication