Moses
Leviticus 10:8ESV·traditional attribution

And the LORD spoke to Aaron, saying,

Matthew Henry Presbyterian @wholebiblehenry

Aaron having been very observant of what God said to him by Moses, now God does him the honour to speak to him immediately (Lev 10:8): The Lord spoke unto Aaron, and the rather because what was now to be said Aaron might perhaps have taken amiss from Moses, as if he had suspected him to have been a gluttonous man and a wine-bibber, so...

Commenting on Leviticus 10:8-11

John Gill Reformed Baptist @doctorgill

And the Lord spake unto Aaron,.... Because he was a prophet, Aben Ezra says; but the reason rather seems to be, because be was the high priest, and now invested with his office, and in the execution of it, and therefore the following law respecting the priest's drinking of wine was given: some say, as the same writer observes, that God spake to him by...

Jamieson-Fausset-Brown Reformed @jfbcommentary

Do not drink wine nor strong drink--This prohibition, and the accompanying admonitions, following immediately the occurrence of so fatal a catastrophe [Lev 10:1-2], has given rise to an opinion entertained by many, that the two disobedient priests were under the influence of intoxication when they committed the offense which was expiated only by their lives.