Passover to Easter:
Have you heard about the ‘Passover’? This is one of the seven feasts of Israel (Read Lev.23). God (Yahweh) designed these feasts to be observed by Israelites. The Hebrew word for feast means ‘appointed times’.
The first feast of the Lord is Passover. It is the fundamental feast which the Jews celebrated the Passover annually since the time of Moses. It occurred sometime around 1446 B.C., in Egypt. It was at that time the 10th plague struck Egypt and their first born were killed by the angel of death. The Jews sacrificed a lamb on the 14th day of the 1st month of the Biblical calendar (called Abib or Nissan) and the blood was applied to on the side door posts and lintel and when the angel of death saw the blood on the door posts, the angel ‘passed over’ that house and the people in that house were saved because the house was protected by the Lamb’s blood, according to the promise given to Moses.
God (Yahweh) established the Passover as a feast to be kept forever (Exo.12:11-14) It was called the ‘Lord’s Passover’ and it was an appointed time to be kept by his people both in the Old and New Testament.
John.1:29 speaks about Messiah as the ‘Lamb of God (Yahweh) which taketh away the sins of the world’. John is referring to the Passover lamb which protected the Israelites from the angel of death, giving them life. The blood of God (Yahweh)’s Lamb is also protecting the believer from hell fire, giving him eternal life.
“Christ (Messiah) our Passover is crucified for us (1 Cor.5:7-8). Let us keep the feast, not with the old leaven of malice and wickedness, but with the unleavened bread of sincerity and truth”. Hear, O believer, keep the feast with sincerity, i.e. honesty and truth or reality. So we are supposed to take part in the new covenant which our Saviour made with his blood. Matt.26:28, ‘This is my blood of the new covenant which is shed for the remission of sins’. Messiah took part in the Passover and instituted the Lord’s supper at that time. (John.13:1-30), which is the new covenant.

In 325 AD, the Roman emperor Constantine convened the Council of Nicea. He wanted to bring as many people as possible into Christianity and also unite the many groups of Christians. It was there that he forbade Christians observing the Passover as a church practice. Since then the holy feasts have not been observed by Christians.

One of the important teachings omitted from the Nicene Creed was the observance of the ‘Hebrew’ feasts. Some believe that Constantine had seen that God (Yahweh)’ people were blessed as a result of observing the feasts, beginning with Passover, and as result, he stopped their adherence to God (Yahweh)’s command. It was after this that the word Passover came into disuse and was replaced by Easter.
Easter is generally understood to be named after the Babylonian goddess Ishtra, a pagan goddess of fertility. Even today these symbols of fertility are used in celebrating Easter…rabbits, dyed eggs and new clothing, all symbolizing spring and the beginning of the growing season. Constantine wanted to universalize the celebration throughout the Christian world, since both the Passover and Easter season and the pagan celebrations happened during the same time of the year, it seemed simple enough to refer to the time as Easter.  Christian are celebrating the resurrection of Jesus (Yahshua) Christ (Messiah) and not some pagan deity. However erasing the Passover season, and the blessings in observing Passover have been tragic.
Technically we should be still celebrating Passover, part of which is the feast of Firstfruits. Jesus (Yahshua) arose during the Feast of Firstfruits. In 1 Cor15:23, Paul even refers to ‘Christ (Messiah) the firstfruits.’ Jesus (Yahshua) Christ (Messiah), our Messiah, was raised on the first day of the feast of firstfruits, the last feast that he took part while on earth.
Regardless, since325 AD, celebrating the Passover and the other holy feasts as mentioned in the Bible has not been a part of church knowledge until these latter days.
Paul was not one of the original twelve Apostles, but was chosen by Jesus (Yahshua) after the resurrection. In fact, Paul led a persecution against the early Christian converts, having many arrested. But on the road to Damascus the glorified Jesus (Yahshua) struck Paul blind and revealed to him that He had indeed been the Messiah and commissioned him as Apostle to the Gentile converts. All but one of Paul's letters to the Churches were to predominately Gentile congregations. Paul was not only teaching Gentile Christians to observe the Passover, but to "Celebrate the Feast" of UNLEAVENED BREAD which follows it. How can we know that Jesus (Yahshua) instructed Paul to teach its observance? We will soon see in 1 Cor.11: 23-34. Paul said that he "DELIVERED" to the Gentile converts that which he had "RECEIVED" from the Lord. It is a memorial of the Lord's death. The memorial is 14th Nissan, the Passover, the same day the first Passover lamb was slain in Egypt which foreshadowed the blessed Lamb to come. Remember Paul instructing them to "Celebrate the Feast" of Unleavened Bread earlier in his letter? This shows when they were partaking of the Bread and the Wine,- it was at Passover. Notice also that this is the "New Covenant" ceremony for Christians to observe, in its appointed time. On that first Passover in Egypt, a lamb was slain, its blood smeared on the front of the Israelites homes to protect them from DEATH which would pass through the land THAT EVENING. More than 1000 years later, a Lamb called Jesus (Yahshua) gave His life on this very day, the Passover, the Lord's appointed time to spill the precious blood that would save the world.