Euthanasia
Euthanasia, the idea that an individual in extreme suffering has a 'right' to die to spare their torment, is in direct opposition to the Bible's teaching. The Bible makes it clear in numerous places that humans have intrinsic value, being made in the image of God. We bear God's 'stamp' of craftsmanship, and so to kill a person is to offend and mock the God who crafted them. A human's life has value regardless of the status, character, race, religion, or sufferring of that person.
Proponents of euthanasia argue that the governing factor is a person's 'quality of life', and that extreme suffering can degrade a person's quality of life to the point where it would be better off if they were dead. In this world-view, the goal of life is happinness, and if sufferring makes a person's life miserable, then it is pointless to continue living. The logical conclusion of this view is dangerous - that human life has no intrinsic value; the only value it has depends on the circumstances - whether you have a happy life, whether you are successful, etc. If you think this way, then of course euthanasia becomes reasonable, because human life has no real meaning. Involuntary euthanasia would also be acceptable, as would be suicide.
Society has replaced a God-centred value system with an empty philosophy which gives no real value to human life. Christians, however, know that man is made in God's image, and has value regardless of the circumstances. We therefore have no room to compromise on euthanasia. God is the life-giver and life-taker, and it is up to him alone to decide when to take a life and end someone's suffering.