The Bible teaches about this, go to our Bible quiz page and test your knowledge about it.
God, Jesus and the Holy Ghost (the Holy Trinity) are merciful, loving beings whose "work and glory [is] to bring to pass the immortality and eternal life of man Moses 1:39. For their mercy to take effect, we have to repent of our wrongdoings and endeavor to change our lives for the good.
The Holy Trinity is one in purpose; however they are separate beings as evidenced in the baptism of Jesus. As it says in Matthew 3:16-17, when Jesus was baptized, the Holy Ghost descended from heaven like a dove, then the voice of God the Father was heard saying of Jesus Christ, "This is my beloved son, in whom I am well pleased."
In Doctrine and Covenants 130:22 it states, "The Father has a body of flesh and bones as tangible as man's; the Son also; but the Holy Ghost has not a body of flesh and bones, but is a personage of Spirit. Were it not so, the Holy Ghost could not dwell in us."
The members of the Holy Trinity live and reign in heaven. If we live righteous lives and have faith in God and in Jesus Christ, we can return to heaven to be with them after this life. In John 5:29, it declares, "And shall come forth [after death; they that have done good, unto the resurrection of life; and they that have done evil, unto the resurrection of damnation."