注大乘入楞伽經 8.174

8.174

純是金沙無有瓦石，以比如來法身。無有生死生滅等沙，謂如來三有生因悉斷。

Being pure golden sand without tiles and stones is used to compare to the Tathāgata's Dharmakāya. Free from the sand of birth, death, arising, and ceasing means that the Tathāgata's causes of birth in the three realms of existence have all been severed.