Are Seventh-day Adventists Christians?

Answer:
According to the official Adventist theology, Seventh-day Adventists (SDAs) worship "Jesus Christ". This version of "Jesus Christ" when officially described by SDAs include facts or a nature not contained or recorded in the original Scriptures. Example are their distinct teaching that Jesus Christ did NOT (i) complete the work of Atonement on the Cross, (ii) that Jesus had a fallen nature, (iii) Satan and NOT Jesus is the final bearer of sins.
These doctrine are based on proof-texting and the eisegesis of Scripture by their Churches prophet Ellen G White.

In the prevailing circles of Orthodox Christians there is still no concensus whether Seventh-Day Adventists are Christians, unlike there is the other Orthodox Denominations ad churches, hence it is still debated whether their doctrines are Christian.
In addition to the some of the primary beliefs of Orthodox Christianity, Adventists also believe--
  • Christians are required to observe the Sabbath which is CLEARLY commanded solely of the Israelites (see, Exodus Chapter 20:2, Exodus 31:17, Deuteronomy 5:15, Ezekiel 20:10-12)
    • Despite any clear and concise Scripture regarding this point, "Seventh-Day" Adventists (SDAs )hold that worship on Sunday (Lord's Day) is "The Mark of the Beast" and Sabbath Observance is indicative of the Seal of God.
    • The anti-Christ is the Catholic Church (as an institution) headed by the Papacy.
    • Despite the fact there have been NO laws OUTLAWING church attendant on the Jewish Sabbath, since their inception SDAs teach "The last days include religious persecution against Sabbath keepers of which the hold protection of Christian Church attendance on the Lord's Day is proof.
  • Contrary to exposition and exegesis of the Original Scriptures SDAs alone with Jehova-Witnesses teach Psychopannychia (aka Soul Sleep--the soul ceases to exists while the body rots in the grave)
    • Reject the teaching of an eternal hell.
    • In the ultimate and total annihilation of the Satan, his angels and the wicked in the lake of fire.
  • Despite the original founders of their Doctrines of an Investigative Judgment & Physical Heavenly Sanctuary, ultimately rejecting these doctrines and lack of support in Scriptures SDA's teach
    • That Christ's death on the cross ONLY only covered our sins and was not sufficient for Jesus to finish His work
    • The final cleansing of sins ONLY began in 1844 (Investigative Judgement) and is currently ongoing in a physical Heavenly Sanctuary and will continue until just before the Second Coming.
  • Despite the SDAs institutions own documents contained in their vaults (e.g., Transcripts of 1919 Bible Conference) which clearly demonstrated the early church Pioneers familiar with EGW knew she was not inspired, still teach Ellen G. White is an inspired writer. Attributing special revelations from God for his church during these last days, similar to the Mormon Joseph Smith, Christian Science's Mary Baker Eddy, and Scientology's L Ron Hubbard.
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First answer by Johnellishartford. Last edit by Wiredog. Contributor trust: 1 [recommend contributor recommended]. Question popularity: 4 [recommend question].