God gave to Moses seven days. These days describe God's plan of redemption. The Spring Feasts of  Passover, Unleavened Bread and Firstfruits were fulfilled with the death, burial and resurrection of Jesus Christ. Weeks was fulfilled the day God gave the Law to Moses and the Holy Spirit to the Church at Pentecost. The last three feasts are fulfilled with the return of Jesus Christ. These days are the seven days of God.

For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures; And that he was buried, and that he rose again the third day according to the scriptures (1 Corinthians 15:3-4).

Teshuvah - Return & Repent

Before Trumpets, Atonement and Tabernacles, there is a time of Teshuvah. After forty days, Moses cut two tablets and returned to God a second forty days. Teshuvah means to repent and return. During the Hebrew month of Elul at the end of morning prayers, the shofar is blown. While Moses was on Mt. Sinai, the people wake up, review their lives and prepare for the high holy days. They repent of their sins to God and others and change their ways.

The Lord said unto Moses, Hew two tables of stone like the first: and I will write upon these tables the words that were in the first tables, which you broke. And he was there with the Lord forty days and forty nights; he did neither eat bread, nor drink water. And he wrote upon the tables the words of the covenant, the ten commandments (Exodus 34:1, 28).

Tishri - New Year

The Jewish month of Tishri is the beginning and the end. It is the first month of the civil calendar and the seventh month of the religious calendar. Tishri means beginning. The first book of the Bible is Genesis or Aleph b'Tishri. Jewish tradition says Adam was created on the 1st of Tishri. God created the world in six days and He rested the seventh so man rules 6000 years and then Jesus Christ rules 1000 years. When time comes full circle, Tishri is the beginning and end of time.

In Tishri [the beginning, Aleph b'Tishri] God created the heaven and the earth (Genesis 1:1).

Feast of Trumpets

The Feast of Trumpets is on the 1st of Tishri. It literally means the day of shouting. The shofar or trumpet is sounded a hundred times and the last trump is the Tekiah Gedolah (1 Corinthians 15:52). Rosh Hashanah or the new year begins after the first sighting of the new crescent moon. Lunar months are 29 or 30 days and set by observation, so no one knew the day or hour until two witnesses saw the first sliver of the moon and testified before the Sanhedrin. In September 2018, the Jewish year is 5779 but because of a ~210 year error, there are about 5989 years from creation. The Feast of Trumpets is fulfilled on the resurrection and rapture day.

For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord (1 Thessalonians 4:16-17).
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Day of Atonement

The Day of Atonement is on the 10th of Tishri and is the most holy day of the year. After forty days, Moses came down from Mt. Sinai with the second set of tablets at the end of Teshuvah. This is the only day the High Priest enters the temple's Holy Place. He sacrifices a ram, bull and goat then sprinkles the blood on the Ark of the Covenant. This is a day of national repentance and forgiveness for the sins of Israel. The Jewish people observe a twenty-five hour fast of food and water. Atonement is fulfilled on the Second Coming of Jesus Christ.

I will pour upon the house of David, and upon the inhabitants of Jerusalem, the spirit of grace and of supplications: and they shall look upon me whom they have pierced, and they shall mourn for him, as one mourns for his only son, and shall be in bitterness for him, as one that is in bitterness for his firstborn (Zechariah 12:10).
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Feast of Tabernacles

The Feast of Tabernacles is the 15th to 21st of Tishri. It is a joyous celebration of the presence of God. On Tabernacles, the first Jewish temple was dedicated by Solomon and the Spirit of God entered the temple. God the Father dwelt in the tabernacle and temple. Jesus Christ was conceived on  Hanukkah but was born on Trumpets or Tabernacles. See First Coming. God the Holy Spirit dwells within Christians today. During Tabernacles, the people live in booths. The Feast of Tabernacles is fulfilled when God the Son begins His reign as God dwells with humanity during the future Millennium.

Behold, the tabernacle of God is with men, and he will dwell with them, and they shall be his people, and God himself shall be with them, and be their God (Revelation 21:3).

The seven days of God are God's plan for the redemption of humanity and the return of Jesus Christ. Four days were fulfill on exact days in the spring so three future days will be fulfilled on exact days in the month of Tishri. Trumpets is the Rapture, Atonement is the Second Coming and Tabernacles is the reign of Jesus Christ.

Let no man judge you in meat, or in drink, or in respect of an holy day, or of the new moon, or of the sabbath days: Which are a shadow of things to come; but the reality is Christ (Colossians 2:16-17).

References: 21st Century Revelation: World Wars, Iraq Wars & End Wars - Chapter 10: Seven Days of God, Chapter 11: Feast of Trumpets, Chapter 12: Fall Jewish Feasts, Spring Feasts, Pentecost, Jewish Calendar, Calendar, Bible Chronology, Revelation Outline, Covenant, Tribulation, Revelation, 21st Century View, Daniel, America, Timeline of the Tribulation, Seven Festivals of the Messiah