Dharma Master Jingjie
Our present life, in the context of the alaya consciousness, is merely like a single bubble in a vast ocean (of countless past lives). If this ocean is polluted, does it matter even if this single bubble is clean? Therefore, your present life is just a snapshot of your entire existence, do you understand?
From the perspective of the alaya-consciousness, practicing well in just this present life is merely one pure bubble among countless (impure) karmic seeds. Truthfully, if you do not rely on Amitabha’s power and maintain right mindfulness (at the point of death), your virtue in this life can become utterly insignificant (in the face of these karmic seeds). Of course, when I say this, I hope it will not damage your faith, but it is the truth.
No matter how well you practice in your life now, you must prevent deluded thoughts from arising at the point of dying. I am being very practical here. You cannot afford to be confused or deluded when dying.
The reason is that while you are creating many karmic seeds for rebirth in Sukhavati now, you have astronomically more karmic seeds for samsara (lying dormant in your alaya-consciousness), far outnumbering the seeds for Sukhavati by many orders of magnitude. Should the (seeds in the) alaya consciousness manifest, then it is no longer a contest limited to this present life, do you know that? That is when accounting for all past lives is laid out before you.
Do you know what the alaya-consciousness is? It is a vast storehouse where every act you have done, every word you have spoken, every thought you have given rise to over countless eons of past lives are unerringly and completely recorded… Do you think the thoughts of aspiration directed towards Sukhavati could ever outnumber those directed towards samsara? I think it is quite unlikely. Let alone past lives, it is quite unlikely even if we only consider our present life.
Therefore, we cannot compete with the alaya-consciousness in terms of karmic force. If you try to compare by the sheer quantity of seeds, you have no hope of winning this battle! Right now, what we need to rely on is the sixth consciousness (mind-consciousness), which is to say that I must maintain control (mindfulness) at the point of dying. Although my seeds for rebirth in Sukhavati are few, I must not trigger the latent negative (samsaric) karmic seeds or karmic forces lying dormant in the alaya-consciousness.
Hence, if a person enters a state of deep sleep or coma at the point of death, it is quite disastrous. They must not be allowed to fall asleep. This is why morphine (or painkillers) should not be administered. If the mind-consciousness enters a sleep state at the end of life, it is over. You have completely lost your advantage or bargaining chip, the alaya-consciousness takes over complete control and it becomes next to impossible for you to go to Sukhavati.
Let me tell you, if your mind-consciousness enters a state of deep sleep, I am definite that there is a 99.9 percent chance that you will not attain rebirth in Sukhavati. That last 0.1% is just to console you! Without the mind-consciousness to direct them, your seeds for Sukhavati cannot be activated! When it comes to karmic strength (in the alaya-consciousness), if you want to compare which is stronger, the karmic force of birth and death (samsara) is infinitely stronger than the karmic force for Sukhavati.
Therefore, you must not allow your mind-consciousness to be lost at the end of your life! Because you need it to direct your karmic force and to propel your aspirations. The mind-consciousness must remain clear. If the mind-consciousness is absent, I am sorry to say, you are finished, you have no hope—frankly speaking, it is hopeless. If a person falls asleep at the end of their life, it is over; entering a coma means it is completely over (in terms of taking rebirth in Sukhavati).
Although in terms of the strength of karmic force and the quantity of seeds, our karmic seeds for Sukhavati are at a disadvantage, you can leverage the use of the mind-consciousness to be mindful (at the crucial juncture of dying). By utilizing the mind-consciousness to recall and recite Amitabha, you activate seeds for Sukhavati even though they are outnumbered— that is your only hope.
Therefore, this is called 'rebirth by the force of mindfulness', rather than 'rebirth by the force of karma'. Why must the mind sustain the practice of concentration and introspection all the time? It is because everything depends on the mind-consciousness at the end of our lives.
Note: There are cases where the comatose patient retains subtle consciousness. Such cases should be considered separately. What is referred to above is a total black-out of consciousness in a comatose patient.