俱舍論頌疏論本 29.16

29.16

四無色定善者，四無色解脫以善定為體，非無記染，非解脫故，亦非散善，性微劣故。無色散善者，如命終心也。

"Four are virtuous immaterial absorptions": the four immaterial liberations take virtuous concentration as their essential nature. They are neither neutral nor defiled, because they are liberations; nor are they non-concentrated virtue, because their nature is weak and inferior. Immaterial non-concentrated virtue refers to such as the mind at the moment of death.