This song is from the British poet Blake's "Innocent Prophecy"
Full text
One sand and one world,
One flower and one paradise .
Holding infinity in both hands,
A moment is eternity.
One grain of sand is one world,
one flower is one paradise,
one tree is one Bodhi,
one leaf is one Tathagata.
Innocent prophecy,
Understand the verses of thousands of years.
It shows that everyone is a flower, and every flower has its own world; everyone is a leaf, and every leaf has its own greenness. When the flowers are about to wither, when the leaves are about to wither. We should all return everything to the earth at the last moment.