It is a very complicated issue especially for pureland
buddhists. To put it simply, there is this school to train
boddisattvas in the West called Sukavathi, the schoool's headmaster
is Amitabha Buddha with 2 vice principals (观音,势至)
What the school offers:
1. Once u enter the schoool, you will never drop out from that
school. Becoming a Buddha is guaranteed (but take some time
lah)
2. Once you attain 八地 boddisattvas, you will be fit to come back
to this world to help others (by manifesting as human, animal,
king, god, priest, pastor blah blah). And you can manifest as
thousands of bodies in thousands of worlds at the same time.
3. There are 9 stages in that school, direct entry into higher
stages are possible depend on how good is your practise
Pre-requisites for entry to this school
1. Reciting the name of Amitabha (there are other methods but
this is the easiest) with strong concentrated mind (you are
guaranteed to be reborn there if you manage to achieve
samadhi 一心不乱) at the moment of death. Obviously you need to
practise before you die.
2. You must detach yourself from all worldly desire and
attachment (attachment to your son, your money etc) at the moment
of death. Obviously you must practise this also before you die
3. You must be good Mahayana Buddhists by helping others as much
as you can (cultivation of 善根, 福德, 因缘)
But most people are not able to achieve samadhi. So at the
moment of death, it is crucial to gather monks/other believers to
motivate you (recite Amitabha Buddha, ask you to forget about your
worldly attachment etc). This process is known as
助念
So obviously, the organ harvesting process while it is the
Mahayana way, will interfere with this process of 助念
...