Moses
Deuteronomy 1:9ESV·traditional attribution

“At that time I said to you, ‘I am not able to bear you by myself.

John Calvin Reformed @genevareformer

9. And I spoke unto you at that time. He does not here say that the counsel was suggested to him from another quarter, as to the appointment of the judges; but, perhaps, he dared not mention any name to these proud and perverse people, lest they should reject the thing which was otherwise good, from dislike of its author, as a foreigner.

Matthew Henry Presbyterian @wholebiblehenry

Moses here reminds them of the happy constitution of their government, which was such as might make them all safe and easy if it was not their own fault. When good laws were given them good men were entrusted with the execution of them, which, as it was an instance of God's goodness to them, so it was of the care of Moses concerning them...

Commenting on Deuteronomy 1:9-18

John Gill Reformed Baptist @doctorgill

And I spake unto you at that time,.... About that time; for it was after the rock in Horeb was smitten, and before they encamped at Mount Sinai, that Jethro gave the advice which Moses took, and proceeded on it, as here related; see Exo 18:1. saying, I am not able to bear you myself alone; to rule and govern them, judge and determine matters between them.