In 1914, after Germany invaded Belgium, a magazine had a famous cartoon in which it showed the German Emperor saying to King Albert of Belgium, “So now you have lost everything”; and Albert’s answer came: “But not my soul!”
Behind this cartoon there is an important teaching that is also in the Gospel: We, human beings, are able to harm others, even to the point of killing each other, but we cannot touch the soul. That is why Jesus says that we must not be afraid of those who kill the body (Lk 12:4) because they cannot kill the soul. Man’s power over man is strictly limited to our bodily life. Our influence over the soul and spiritual faculties of others is limited to the permission of others. For example: someone can motivate me to hate someone, but he cannot force or oblige me to hate someone; hate depends on me since it is an action of my soul.
Something similar happens with our freedom. Someone can limit some aspect of our freedom, for example: if a thief goes to jail, the police is limiting his freedom of movement, but that thief continues to be free. In fact, there are thieves that continue to steal from jail, through their men. Someone can limit freedom of speech, market freedom, political freedom, etc. because these freedoms are related with our body. They are limiting our body: legs, mouth, etc. but they cannot touch our real freedom, since they cannot touch our soul. Any restriction someone can impose on us cannot limit or restrain the essential act of freedom, which is love.
Physical evil, or suffering, is not the worst evil we can suffer, even if that evil will cause our death, because with death that evil will end while our life will not. This is why Jesus says that we must not be afraid of those who can kill the body: illness, people, etc. since those things are temporary and sooner or later, they will end. They could end during this life or perhaps not, but for sure they will end after this life, once we arrive to eternal life, there shall be no more death or mourning, wailing or pain, for the old order has passed away (Rev 21:4).
So, whom should I fear? We must fear moral evil which is able to kill our soul, or rather, the supernatural life in our soul. Why should I fear moral evil? Because, moral evil could remain forever, as Jesus also says: Be afraid of the one who after killing has the power to cast into Gehenna (Lk 12:5). Moral evil is sin and sin is against love, any kind of love: love of God, love of myself, love of my neighbor.
This important teaching completely changes the way we should look at life here on earth. The human vision of life is this: enjoy as much as possible, avoid suffering as much as possible. The Gospel vision of life is this: avoid sin as much as possible, love God as much as possible. Suffering and difficulties should be a means for us to love God, rather than a means for us to sin.