Kornfield J, Breiter P. "A still forest pool. The insight meditation of Achaan Chah." Quest Books, Wheaton IL, 1985.
As such, the object of the path is awareness and not clinging to anything. But initially, our objective is not clinging to that which is unsatisfactory, stressful and doesn't belong to us. Joseph Goldstein
So what can we hold onto?
“If you let go a little, you will have a little peace.
If you let go a lot, you will have a lot of peace.
And if you let go completely, you will have complete peace.”
Ajahn Chah. “The Collected Teachings of Ajahn Chah - Single Volume.” iBooks. https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=4CEF53DF37C241A3AE9327D1D40921BD
See also: http://www.johnlovas.com/2014/10/two-levels-of-practice.html
Rays of light are ephemeral; other things less obviously so.