Paul has been arrested and is facing death.  He writes his last letter to his spiritual son Timothy while in chains.  I imagine he choose his words carefully since he most likely would not see him again. Everyone who preached Jesus Christ crucified and risen from the dead was in danger of losing his life. That meant Timothy's life was also in danger.

Knowing the emotional struggle of facing death, Paul writes, "for God has not given us a spirit of fear; but of power, and of love and of a sound mind.  So do not be ashamed of the testimony of our Lord, nor of me his prisoner, but share in the afflictions of the gospel according to the power of God" (2 Timothy 1:7).

Our natural inclination is to fear and the enemy of our soul is quick to use that particular weapon against us.  Our faith in God will quickly extinguish that fiery dart (Ephesians 6:16; Psalm 91:5-6).