Moses
Genesis 10:25ESV·traditional attribution

To Eber were born two sons: the name of the one was Peleg, for in his days the earth was divided, and his brother’s name was Joktan.

Matthew Henry Presbyterian @wholebiblehenry

Two things especially are observable in this account of the posterity of Shem: - I. The description of Shem, Gen 10:21. We have not only his name, Shem, which signifies a name, but two titles to distinguish him by: - 1. He was the father of all the children of Eber.

Commenting on Genesis 10:21-32

John Gill Reformed Baptist @doctorgill

And unto Eber were born two sons: the name of one was Peleg,.... Bochart (k) thinks, that either Peleg, or one of his posterity, in memory of him, gave the name of Phalga to a town situated on the Euphrates; though the reason of the name, as given by Arrianus, as he himself observes, was because it divided between the two Seleucias, as the reason...

Jamieson-Fausset-Brown Reformed @jfbcommentary

Peleg; for in his days was the earth divided--After the flood (Gen 11:10-16) the descendants of Noah settled at pleasure and enjoyed the produce of the undivided soil. But according to divine instruction, made probably through Eber, who seems to have been distinguished for piety or a prophetic character, the earth was divided and his son's name, "Peleg," was given in memory of that event (see Deu 32:8; Act 17:26).