Charles Ellicott Commentary Isaiah 63:3

"I have trodden the winepress alone; and of the peoples there was no man with me: yea, I trod them in mine anger, and trampled them in my wrath; and their lifeblood is sprinkled upon my garments, and I have stained all my raiment." — Isaiah 63:3 (ASV)

I have trodden the winepress alone ... — The “winepress” here, as elsewhere (Joel 3:13; Lamentations 1:15; Revelation 14:18–20), is the accepted symbol of the carnage of battle. What the hero-conqueror asserts is that he fought the battle single-handedly. He had no human allies, but God was with him.

A slight change in the vowel-points, adopted by some interpreters, changes the verbs to the future tense: “I will tread ... will trample, ... ” as in the second clause of the Authorized Version. It is perhaps better to take the latter verb also as in the past. The work of slaughter is clearly thought of as accomplished before the warrior is seen.