From the very beginning of his priesthood, Father Daniel chose the most difficult form of ministry—missionary outreach, which was initiated by the Apostles. In the early Church, missionary work was identical with martyrdom. “The martyrs were preachers of Christianity, continuers of the Apostolic ministry; and this mission they fulfilled precisely as martyrs*, that is, presenting themselves as witnesses.” (Bolotov V.V., Lectures on the History of the Early Church. 1. The Post-Apostolic Church and the Roman Empire. in Russian). After the Bolsheviks seized power in 1918, their first blow was directed specifically against missionaries. Murdered were the missionary Bishop Ephrem Kuznetsov, Protopriests John Kochurov, John Vostorgov, Konstantin Golubev, diocesan missionary Nicholas Varzhansky and other such missionaries. [*martyrs: the Greek root μάρτυς (martys) means “witnesss”.]
Father Daniel Sysoev carried out his missionary activity among Moslems. His Evangelical preaching was very successful: He converted and baptized many people; he received death-threats in response. His answer to such threats was to preach Christ with still greater zeal. Therefore his death is a Christian sacrifice for the sake of the great cause to which he felt called by Jesus Christ. Such a death is an open and manifest victory, because “warriors for Christ are not killed, but crowned” (St Cyprian of Carthage, hieromartyr. Epistle 66).
The early Christians referred to the day of death of their brothers and sisters in the faith as their birthday—birth into a new life. With the coming to earth of the Saviour, mankind’s relationship with death was changed forever. “If we believe in Christ, and if through faith in His word and promises we shall never die, then we ought with joyful daring to go to Christ, by Whom and with Whom we shall live and reign forever. It is through temporal death that we cross over to immortality; and eternal life can begin for us only after our departure from here. And this is not really a departure but only a crossing over or resettlement into eternity after our temporal sojourn on earth. Who would not hasten to cross over to that which is better? Who would not desire to be changed and transfigured according to the image of Christ and the sooner to partake of heavenly glory?” (St Cyprian of Carthage, hieromartyr. Book on Mortality).
To him (or her) who dedicates himself to the service of Christ are given various means to bring people to the Truth: preaching by word, and preaching by one’s life as a living example of self-sacrificing service. These earthly labors for Father Daniel have ended. There remains the brightest and most powerful preaching: the preaching of death. “From henceforth, blessed are the dead who die in the Lord: Yea, saith the Spirit, they shall rest from their labours; for their works do follow them” (Revelation 14:13).
 Fr. Daniel Sysoev was short dead in his church in Moscow on November 19th, 2009.