Hebrews 2:14-16 (ESV)
Since therefore the children share in flesh and blood, he himself likewise partook of the same things, that through death he might destroy the one who has the power of death, that is, the devil,  and deliver all those who through fear of death were subject to lifelong slavery.  For surely it is not angels that he helps, but he helps the offspring of Abraham
This text tells us two things that the death of Christ accomplished. 1) He destroyed the one who has the power of death, and 2) He delivers those who were subject to lifelong slavery.
Before we came to Christ we were slaves. Slaves to sin, slaves to death, slaves to thinking that the wrong things mattered. This slavery, the text says, was due to fear of death. Jesus erases the fear of death. Dying is not the end. It is entrance into the presence of Christ. Once the fear of death is removed there is nothing left to fear. The fear of death brings livelong slavery. It hinders people from really living.
Satan wields the concept of death as a weapon before people to keep them in a state of fear and Jesus has removed it and this should make our hearts sing. Christians are those who have been set free. They have been set free from sin and all its consequences. They have been liberated to true life.
People who have been set free do not live in the chains from which they were released. They leave them behind. Now that the constricting fear of death is removed there is great liberty. We know that death is not the end. We can serve God without fear of the consequences. Though an army encamp against us we will not fear.
In Luke 12:4 we have the account of Jesus telling His disciples that they should not fear those who can kill the body and after that do no more. In other words – all they can do is kill you, and we do not need to fear those who can only do that little thing. All they can do is usher us into the presence of the One who won the victory for us. If they let us go, we serve Christ. If they enslave us we worship from our hearts. If they destroy all that we have and who belongs to us, yet will we worship Him.
He has defeated our fear. What a work Christ has done.