Solomon
Ecclesiastes 9:5ESV·traditional attribution

For the living know that they will die, but the dead know nothing, and they have no more reward, for the memory of them is forgotten.

Matthew Henry Presbyterian @wholebiblehenry

Solomon, in a fret, had praised the dead more than the living (Ecc 4:2); but here, considering the advantages of life to prepare for death and make sure the hope of a better life, he seems to be of another mind. I. He shows the advantages which the living have above those that are dead, Ecc 9:4-6. 1. While there is life there is hope.

Commenting on Ecclesiastes 9:4-10

John Gill Reformed Baptist @doctorgill

For the living know that they shall die,.... Death is certain, it is the demerit of sin, the appointment of God and the time of it is fixed; it may be known that it will be, from the word of God that assures it, from all experience which confirms it, and from the decline of nature, and the seeds of death in men.

Jamieson-Fausset-Brown Reformed @jfbcommentary

know that they shall die--and may thereby be led "so to number their days, that they may apply their hearts to wisdom" (Ecc 7:1-4; Psa 90:12). dead know not anything--that is, so far as their bodily senses and worldly affairs are concerned (Job 14:21; Isa 63:16); also, they know no door of repentance open to them, such as is to all on earth. neither . . .