You’ve just returned from the hospital. Your 86-year-old father has been diagnosed with cancer, and you’re trying to decide if he should undergo chemotherapy. He isn’t keen. He says he’s had a good life and wants to join his Savior. But he’s your dad. How do you decide what to do? How does the Bible guide us?

Our behavior consists of motivation to act, which influences our intentions, which informs our actions, which have consequences. As Christians, we use the Bible as our moral compass. Christian motivation is grounded in the summary of the commandments given by Jesus in Matthew 22:37-40: “Love the Lord your God with all your heart and with all your soul and with all your mind” and “Love your neighbour as yourself.” Jesus told us that our actions reflect what is in our hearts and minds (Mark 7:21-23), so both intentions and actions will be morally significant. Consequences are important too, and we do need to consider them as we will be concerned how our actions affect our neighbours.

So, back to Dad in hospital. What to do?

First, in modern medical care, mentally competent individuals can make their own medical decisions. God does give us life and take it away, but in our dominion of the earth we have developed technology that affects its timing. When making these decisions, it is helpful to understand what the treatment actually involves. I encourage my patients to consider the burden and benefits of treatment. If the treatment is overly burdensome (for example, because of side effects of chemotherapy), it may cancel out any benefit obtained through treatment (such as prolonged life). This is a morally acceptable equation for Christians. Your father may well want to discuss the treatment possibilities with you, but in the end, if he is mentally competent, it is his decision.

We have a generous God who gives us choices. We are wise to seek counsel when unsure, but in the end we take responsibility for our decisions in this life. Is your father able to understand the implications of having and not having chemotherapy? If so, you really don’t have a problem. Nowhere in the Bible does it say we should do everything we can to prolong life as much as possible. In fact, to do so would be to treat life itself as an idol. At the same time, we do need to consider the consequences of our actions. We are instructed to be good stewards, but while this demand may affect the decision-making of a young mother in considering the responsibilities of her earthly presence, it is unlikely to change your father’s position.

But what if your parent is not mentally competent?

My mother has told me she wants me to be her surrogate for decision making should she get sick. But such arrangements should only come into play when the patient cannot speak for herself. And when I am asked for my opinion, it is not my responsibility to decide what is best for her (even though I am a physician). My role is to tell the doctors what she would have said if she were able to say it for herself. Obviously, this role requires me to know her preferences, and this is why we should try harder to talk about end-of-life issues with our loved ones. It can be hard, but is enormously helpful in a crisis. I have known people who have felt like their parents’ executioners when halting life-sustaining treatment that failed to change the course of an illness. This is painful and unnecessary, and usually reflects the wrong interpretation of the surrogate decision-making role.

There are systems in place to help those around us know what we would want for ourselves in future medical care. Advanced care directives, also known as living wills, are a written record of our preferences. Personally I would rather just let my family know what is important to me, as it is difficult to cover all scenarios in a written document (a situation which, as a physician, I have found quite tricky at times). If you do decide to go down the document route, I would advise you to review it every year or so, as we all change our minds over time about medical care. Everyone—particularly the elderly and unwell—should do something to help their families understand their thinking on these matters.

If your father is not mentally competent, and you have the responsibility to decide the course of treatment, you need to think about what he would have wanted, based on his words in the past and the present. It is understandable that a Christian with a terminal illness sees death as a gain (Phil. 1:23). We have to watch our motivation and make sure that in our love for others we are not selfish in our advice.

What if your parent is not saved? This is an understandable concern. While we always want to make sure our loved ones have heard the gospel, in my experience as a hospice physician, if someone has been saying no to God all his life, it is unlikely that artificially prolonging life will make a difference. Some people do become Christians late in the day. My father did. And I traveled to visit my grandmother in her final illness just to make sure she had really heard the gospel even though she could not respond. But it is hard to see the benefit of holding on and waiting for a change of heart in one you have prayed for for years.

Losing loved ones is always hard, even when it is expected. Death is an enemy for now, but our future hope is sure (Rev. 21:4).

Editors' note: For further reading on this subject, check out Glimpses of Heaven: True Stories of Hope and Peace at the End of Life's Journey by Trudy Harris.