The average Christian believes that there is Jehovah (God), good, and Satan, bad. These are the two polar opposites on an axis of morality. Man falls somewhere between these two extremes, the position depending on the decency of his character. As man we are unable to inhabit the utmost end of either side of this axis. By necessity we remain in the 'grey area', for if we were to reach either of the ends where God or Satan are denoted, we become one with these points as the absoluteness of these two transcend duality on their respective ends of the spectrum. Even the apotheosis of the saints falls short of being congruent or equal to God. [Of course the more learned scholar will see God and Devil as two sides of the same coin, being a necessity of equilibrium. Also, my use of the term "God" should not be confused with what others call the Tao, Brahman, the Infinite (Ain Soph), the All, or such others. This is Christianity - God is usually viewed as some anthropomorphic being sitting out of sight, judging our every move and making sure we conform to His idea of 'good' (If the Christian God came down the chimney I would almost expect presents). This Christian idea of God actually pertains to all of the Abrahamic religions.]
If one goes a little further it becomes apparent that God is not merely a single entity, but is in essence three. This three-fold view of God is known as the Holy Trinity. This Trinity consists of the Father, the Son, and the Holy Ghost. Now it must be understood that these three aspects are not really partitioned beings, rather they are three distinct states of a singular being. The best way to describe this is using the analogy of water. Water exists as solid, liquid and gas. Each of these three phases has different properties, but ultimately they are all water.
The Father is the creative aspect. He is the Creator of the universe and all that sits within it. The Son is the Logos or Word. It is through Him that one is given the opportunity of providence. The Holy Ghost is the resurrection of the spirit. It is the agent that is at work when one gives up his sinful, material existence and has his soul transformed or resurrected in divinity.
Pragmatically:
To have Christ in one's heart means that all doubt of death should be extirpated from one's soul. Death is not to be feared, because of the assurance of Heaven through the redemption of Christ. And as death is the unconditional consequence of all life, there is nothing then that should cause fear. [A basic psychological ploy if you will]
