In this union they can have no share who deny that in the Son of God, Himself true God, man’s nature abides, assailing the health-giving mystery and shutting themselves out from the Easter festival. For, as they dissent from the Gospel and gainsay the Creed, they cannot keep it with us, because although they dare to take to themselves the Christian name, yet they are repelled by every creature who has Christ for his Head. For you rightly exult and devoutly rejoice in this sacred season as those who, admitting no falsehood into the Truth, have no doubt about Christ’s birth according to the flesh, His Passion and Death, and the Resurrection of His body: inasmuch as without any separation of the Godhead you acknowledge a Christ, Who was truly born of a Virgin’s womb, truly hung on the wood of the cross, truly laid in an earthly tomb, truly raised in glory, truly set on the right hand of the Father’s majesty. ‘Whence also’, as the Apostle says, ‘we look for a Saviour our Lord Jesus Christ. Who shall refashion the body of our humility to become conformed to the body of His glory’, Who liveth and reigneth, together with His Father and the Holy Spirit, now and forever. Amen. — Homily 72, Part VII. Only true believers can keep the Paschal festival.