Jesus teaches us that if we do not fear God we cannot enter into his eternal Kingdom, the goal of spirituality is to attain the likeness of God ("Be perfect, therefore, as your heavenly Father is perfect" Matthew 5:48), and the gift of fear of God is the beginning of that resemblance. There is a true and false fear, we should not fear men but God, this is one of the most important reflections of Jesus. For Jesus the fear of God, and this also comes from the Old Testament, is not a passion but a special attachment to God for his precepts, for his teachings. According to Thomas Aquinas, the spiritual gift of fear of the Lord, one of the seven gifts of the holy spirit, is defined as constancy, firmness, devotion, equanimity, and stability.
The parable of the sower (Matthew 13:1-9) is a clear example of the importance of this spiritual gift. What faith can we have if we do not have constancy in listening and living the word of God? The fear of God is the path to Gnosis (inner enlightenment): "No one can enter the kingdom of God unless they are born of water and the Spirit.", John 3:5.
This is how Jesus speaks to us about that fear that makes us children of God: "I tell you, my friends, do not be afraid of those who kill the body and after that can do no more. But I will show you whom you should fear: Fear him who, after your body has been killed, has authority to throw you into hell. Yes, I tell you, fear him" Luke 12:4-5.
And Jesus in his teaching tells us about something very important, there is a first death and a second death. The first death is the death of the body, and the second death is the death of the soul. Our Lord Jesus does not tell us much about life in the afterlife, but if we are sensible we must avoid the last death. The worst punishment is not that of men but that of God towards those who do not feel fear and reverence for him.