Matthew Poole and continuators on Psalms 75:5

5 Lift not up your horn on high , speak not with a stiff neck .

A Metaphor from untamed and Stiff necked oxen, which will not bow their Heads to receive the yoke, but lift up their Heads and Horns to avoid it. Or, against the High, (i. e.) Against God, who is mentioned under this same Title, Psal. 56. 2. though there it be rendred, most High.

To wit, against me and my Government.

With Pride and Contempt of my Person, and with Rebellion against God's Will declared concerning my Advancement, of which you are not ignorant▪ See 2 Sam. 3. 17, 18.