Question: "What does it mean to believe in the sanctity of life?"
Answer: The phrase “sanctity of life” reflects the belief that, because people are made in God’s image (Genesis 1:26), human life has an inherently sacred attribute that should be protected and respected at all times. While God gave humanity the authority to kill and eat other forms of life (Genesis 9:3), the murdering of other human beings is expressly forbidden, with the penalty being death (Genesis 9:6).
Humanity was created in God’s image, but sin has corrupted that image. There is nothing inherently sacred in fallen man. The sanctity of human life is not due to the fact that we are such wonderful and good beings. The only reason the sanctity of life applies to humanity is the fact that God created us in His image and set us apart for all other forms of life. Although that image has indeed been marred by sin, His image is still present in humanity. We are like God, and that likeness means that human life is always to be treated with dignity and respect.
The sanctity of life means that humanity is more sacred than the rest of creation. Human life is not holy in the same sense that God is holy. Only God is holy in and of Himself. Human life is only holy in the sense of being “set apart” from all other life created by God. Many apply the sanctity of life to issues like abortion and euthanasia, and, while it definitely applies to those issues, it applies to much more. The sanctity of life should motivate us to combat all forms of evil and injustice that are perpetuated against human life. Violence, abuse, oppression, human trafficking, and many other evils are also violations of the sanctity of life.
Beyond the sanctity of life, there is a much better argument against these things: the greatest commandments. In Matthew 22:37-39 Jesus says, "'You shall love the Lord your God with all your heart, and with all your soul, and with all your mind.' This is the great and foremost commandment. The second is like it, 'You shall love your neighbor as yourself.'” In these commandments, we see that our actions are to be motivated by love for God and love for others. If we love God, we will value our own lives as part of God’s plan, to do His will until it comes about that His will is better served by our deaths. And we will love and care for His people (John 21:15-17). We will see to the needs of the elderly and sick. We will protect others from harm—whether from abortion, euthanasia, human trafficking, or other abuses. While the sanctity of life can be the foundation, love must be the motivation.