首楞嚴義疏注經 3.46

3.46

「阿難！譬如有人以舌舐吻，熟舐令勞，其人若病則有苦味，無病之人微有甜觸。由甜與苦顯此舌根不動之時淡性常在，兼舌與勞同是菩提瞪發勞相。」

"Ānanda, it is like a person who licks their lips with their tongue: licking continuously causes fatigue; if the person is ill, there is a bitter taste, and if the person is not ill, there is a slightly sweet sensation. From sweetness and bitterness, it is revealed that when this tongue faculty does not move, the bland nature is constantly present. Both the tongue and the fatigue are together the marks of staring fixedly and producing fatigue within bodhi."