A fertilized egg is indeed a human life. Here are some of the basic biological qualifications for life:
1) Reproduces
2) Has highly ordered structure
3) Energy utilization (Metabolism)
4) Growth and development
5) Response to the environment (stimulus)
6) Possession of a genetic program
Now, having listed the six main characteristics of life, doesn't a developing fertilized egg meet these requirements? A fertilized egg reproduces by means of cell division, and thus also is growing and developing as a result of cellular division. A fertilized egg is also highly ordered in its structure, receives nutrients from its mother (metabolizes), and responds to its environment. And last, but not least, a fertilized egg contains the complete genetic information of a full-grown adult human (which makes the fertilized egg human). If a fertilized egg is a human life, then it cannot be considered simply as property.
It is a lot better than simply not giving the embryo a chance at life. In vitro fertilization is a very expensive procedure and if a couple cannot afford it, taking on another couple's fertilized egg when it is cheaper is a great way to allow them to have the procedure and to give the embryo a chance at life.
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Ephesians 6:11
Put on the full armor of God so that you can take your stand against the devil's schemes.