What were the three times God reveals the divine plan in the Old Testament How does God do this in each case?

Answer 1

Not sure what you mean by 3 times but God does nothing without first revealing it to mankind. He established His 7 Holy/Feast Day Plan to man to show each step of His plan of Salvation. About one year after the Israelites left Egypt, God established a temporary Sacrificial system to help the people understand this better. After Christ came and conquered the god of this world by being sacrificed or Crucified for the sins of all mankind and Resurrection, the need for animal sacrifice ceased. So the first 3 of the 7 Feast Days have been fulfilled with the last 4 awaiting their time to be completed. I will elaborate:

Passover - A memorial to the sacrifice of Jesus our Passover (1Corinthians 5:7)

Days of Unleavened Bread - Pictures putting sin out of our lives (1 Cor. 5:6-8)

Pentecost - Depicts the Church as the firstfruits of salvation (Romans 8:23)

Feast of Trumpets - Celebrates the 2nd Coming (1 Thessalonians 4:16-17)

Day of Atonement - Portrays the binding of Satan for 1,000 yrs (Rev. 20:1-3)

Feast of Tabernacles - Millennial Rule of Christ and firstfruits (Rev 20:4)

Last Great Day - Judgement of mankind (Revelation 20:5; 11-12)