Angnix, often many hours before a terminally ill person leaves they will come back for a short period with lots of energy, wide awake,
or at least there will be lots of activity in their eyes. Loved ones often think that this is a sign that they are getting better, but more times
than not it is as and angelic ground crew has arrived to see that person off. If you are present at the time of his leaving, you might be able
to feel the life leaving his body; that is him leaving.
I have worked in hospices and in hospitals where I witnessed this many times. A big bust of energy from a patient who is dying and then hours
later they are gone. His hanging on, if in fact he is doing that, may just be him attempting to adjust to the changing sensations that occur in
dying. Dying is a process, and some people hang on out of fear or, as some here have already stated, out of concern for loved ones they are
leaving behind.
Have patience and just continue to share your love with him. This is part of your spiritual journey as well. I have sat with people as they died
and it enhanced my spiritual journey. My wife passed from breast cancer, and she hung on for some time.