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Only if the blood has been broken down into smaller parts that we call fractions.
Firstly the 'faithful and discreet' slave are the 10 or so men in Brooklyn that make up our Organization's Governing Body.
These men, the 'faithful and discreet slave' class, tell us not to give or receive whole blood or four main parts of blood, based on their understanding of Acts 15 and therefore we are obeying Jesus' direct commands as explained in the following quote,
Watchtower 1959 1st May p269
''To hold to the headship of Christ, it is therefore necessary to obey the organization that he is personally directing.Doing what the organization says is to do what he says. Resisting the organization is to resist him.''
Although we do not give or donate blood, we are allowed to accept blood that non-Witnesses have donated as long as it has been split into smaller parts that we call fractions.
A Witness would be disfellowshipped and shunned by his fellow Witnesses if it became known that he had willingly taken a transfusion of whole blood, red cells, white cells, plasma or platelets. If these parts are broken down into smaller parts then that would be a personal conscience matter.
For example, whilst red cells are not allowed to be transfused, haemoglobin which makes up only 97% of the dry weight of a red cell is allowed to be transfused as it a smaller part of a red cell.
Whilst these definitions are not in the Bible, we as Jehovah's Witnesses put our trust in the definitions provided by our Governing Body as we believe that we should 'respond to the directions of the ''slave'' [Governing Body] as we would to the voice of God.' Watchtower 15th June 1957 p370.
Any improvements on the above?