The answer
The Master Christ was not referring at all to physical death, for it is assumed that man will die, and will not remain alive forever in this world. He was referring to spiritual death, for the righteous man who keeps the words of his Saviour Jesus Christ will never see death, i.e. will remain alive in the heavenly glories. His body will die, and will be buried in the grave. His spirit, however, will remain alive in the presence of God forever.
The Master Christ said elsewhere, “I am the resurrection, and the life: he that believeth in Me, though he were dead, yet shall he live” (John 11:25). That is, whoever believes in Christ Jesus our Lord, His teachings, that He came to save the world from sin, and to die in order to redeem him on the Wood of the Cross, then he will remain alive in spirit, even if he dies physically. Corporal death is not the ultimate end of things, for the believer sleeps in hope of the Resurrection in the Living Christ, Who is risen from the dead. It is only a departure.
His Holiness Pope Tawadros II
Pope Tawadros II, My Faith: A Series of Dialogues on the Creed (Coptic Orthodox Patriarchate, 2014), 147–148.

