Three times thou shalt keep a feast unto me in the year.
Thou shalt keep the feast of unleavened bread: (thou shalt eat unleavened bread seven days, as I commanded thee, in the time appointed of the month Abib; for in it thou camest out from Egypt: and none shall appear before me empty:)
Salvation, new birth;
1 Corinthians 5:7-8 Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us: Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened bread of sincerity and truth.
John 3:5 Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God.
And the feast of harvest, the firstfruits of thy labours, which thou hast sown in the field:
The baptism into the Holy Spirit;
Acts 1:5 For John truly baptized with water; but ye shall be baptized with the Holy Ghost not many days hence.
And the feast of ingathering, which is in the end of the year, when thou hast gathered in thy labours out of the field.
The mature church;
James 5:7-8 Be patient therefore, brethren, unto the coming of the Lord. Behold, the husbandman waiteth for the precious fruit of the earth, and hath long patience for it, until he receive the early and latter rain. Be ye also patient; stablish your hearts: for the coming of the Lord draweth nigh.
1 Corinthians 13:9-10 For we know in part, and we prophesy in part. But when that which is perfect is come, then that which is in part shall be done away
Ephesians 4:13 Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ:
Three times in the year all thy males shall appear before the Lord GOD.
See; The baptism into the Holy Spirit