The applications of the medical handling of blood or blood-derived products has produced questions such as:
"What about accepting small fractions extracted from a primary component of blood, such as serums containing antibodies to fight a disease or to counteract snake venom since some have concluded that such minute fractions are, in effect, no longer blood?"
"What about a Christian's own blood being handled in the course of a surgical procedure, medical test, or current therapy?"
The Jews surely must have faced similar uncertainties with the eating of meat. The Bible is clear that a person obedient to God would not eat unbled meat. Still, questions might have arisen: When an Israelite killed a sheep, how quickly did he have to drain its blood? Did he have to slit the animal’s throat for drainage? Was it necessary to hang the sheep by its hind legs? For how long? What would he do with a large cow? Even after drainage, some blood might remain in the meat. Could he eat such meat? Who would decide? God offered basic guidance on slaughtering clean animals and draining their blood, but he did not go beyond that.—John 8:32.
So how should a Christian who wishes to "abstain from blood" decide the personal medical handling of their blood and/or whether to accept blood-derived medications?
If a Christian who is sincere in abiding by God's moral principle to blood is uncertain about whether to accept certain procedures related to blood-derived medicine or handling, he should learn what God’s Word says and strive to mold his conscience by it. That will equip him to decide in line with God’s guidance rather than asking someone else to make a decision for him. (Psalm 25:4, 5) He would also carefully consider as much accurate information as possible concerning the procedure(s) in question.
Conscience is the inherent ability to weigh and decide matters, often moral issues. (Romans 2:14, 15) But just because something may be a matter of conscience doesn't mean that it is inconsequential. It can be very serious. If your compromise on this issue would trouble your Bible-trained conscience, ignoring it could not only damage your conscience, but also your relationship with God. That relationship is the only one that can lead to everlasting life, based on the saving power of Jesus’ shed blood. Another reason why it is serious is that it can affect others whose conscience may differ. Take for example, Paul’s advice about meat that might have been presented to an idol and was later sold in a market. A Christian ought to be concerned about not ‘wounding consciences that are weak.’ If he stumbles others, he could ‘ruin his brother for whose sake Christ died’ and be sinning against Christ. So personal decisions on this matter should be taken very seriously.—1 Corinthians 8:8, 11-13; 10:25-31