Is Christadelphianism Christian?
No, Christadelphianism is not Christian. Like all cults, Christadelphianism denies one or more of the essential doctrines of Christianity: Jesus is God, the physical resurrection, and salvation by grace. In this case, it is the deity of Christ and salvation by grace through faith are the problems with this group.
In regards to Jesus, it teaches that....
Of primary importance is what the Christadelphians say about Jesus. They deny He is divine in nature. According to John 1:1,14, John 8:58 (with Exodus 3:14), and Col. 2:9, Jesus is God.
Furthermore, Jesus said in John 8:24, "I said therefore to you, that you shall die in your sins; for unless you believe that I am, you shall die in your sins." Also, John the Apostle said in 1 John 4:2-4, "By this you know the Spirit of God: every spirit that confesses that Jesus Christ has come in the flesh is from God; 3and every spirit that does not confess Jesus is not from God; and this is the spirit of the antichrist, of which you have heard that it is coming, and now it is already in the world." You can see that denying that Jesus has come in the flesh (that He is God in flesh per John 1:1,14), is the spirit of antichrist.
Since we are justified by faith (Rom. 5:1; Eph. 2:8-9), it is crucial to crucial to have the proper object of faith. All Satan has to do is to get someone to believe in a false Jesus and the person is lost (Matt. 24:24). A false Jesus cannot save and only the true Jesus reveals the true God (John 14:6; Luke 10:22; John 17:3). Since Jesus is actually God in flesh (John 1:1,14; 20:28; Col. 2:9; Phil. 2:5-8; Heb. 1:8), it follows that those who deny His divine nature -- and ascribe a sinful one to Him as the Christadelphians do -- cannot have the true Jesus and are, therefore, serving a false God.
Second, the Christadelphians deny the substitutionary atonement of Jesus. They say that He did not take our place on the cross and that He did not bear our sins. This is in direct contradiction to Scripture. 1 Pet. 2:24 says, "He Himself bore our sins in His body on the cross, that we might die to sin and live to righteousness; for by His wounds you were healed." Instead, they teach a kind of representation that was not effective to remove sin and say, "Christ did not die as our substitute, but as our representative" (Answers, p. 25).
Additionally, in Answers, page 24, it says, "But it is equally true that, being 'made sin for us' (2 Cor. 5:21), he himself required a sin offering..." In other words, they are saying that Jesus Himself also needed to be saved. This is absolutely unbiblical and heretical and needs to be labeled for what it is: false doctrine. Jesus was without sin (1 Pet. 2:22), the exact representation of the nature of God (Heb. 1:3). Since God is sinless and Holy, so is Jesus in nature and essence.
Furthermore, the Christadelphians, by having a Jesus who has a sin nature, cannot have a proper sacrifice by which their sins are atoned for. According to the Old Testament, the sacrifice for sins had to be without blemish (Deut. 17:1). Having a sin nature would definitely be a blemish which would invalidate the sacrifice.
Third, the Christadelphians add a work to salvation. They say that baptism is part of the saving process. But, baptism is not necessary for salvation. Instead, it is a representation of the inward reality of regeneration (1 Pet. 3:21), a covenant sign of God's work upon the heart (Col. 2:11-12). Gal. 5:1-12 speaks of the grave error of some people who thought that they needed to partake in some part of the Law (circumcision) to be saved. Paul quickly denounced them with very strong words (Gal. 5:12). Additionally, Rom. 5:1 says that we are justified by faith, not by faith and baptism. Rom. 3:23 says we are saved not by the works of the Law; that is, not by anything that we do. Since our righteous deeds are filthy rags before God (Isaiah 64:6), we must completely rely upon the grace of God for our salvation -- which is by faith in Jesus who is God, the creator, in flesh.
The Christadelphian religion is a false religion. it is definitely not Christian. This is not to say that there are not decent people who intend to serve God honestly and truthfully. But sincerity does not bridge the gap between God and man. Only the blood of the real Jesus does that, not a false Christ with a sin nature who himself needed salvation.