Jesus Christ is both God and the Son of God. He was born of a virgin, lived a sinless life, and physically died on the cross to make payment for the sins of mankind. When He took on a human nature he never ceased to be God; He was both fully God and fully man. He rose from the dead and ascended to heaven, where He acts as the Mediator -- the High Priest -- for believers.
(Matthew 1:23 AMPC; I Corinthians 15:3-4 AMPC; II Corinthians 5:21 AMPC; Matthew 28:6 AMPC; Hebrews 1:3 AMPC)