en_tn/rev/16/04.md

poured out his bowl

See how you translated this in Revelation 16:2.

rivers and the springs of water

This refers to all bodies of fresh water. (See: rc://en/ta/man/translate/figs-synecdoche)

angel of the waters

This refers to third angel. He was in charge of pouring out God's wrath on the rivers and the springs of water.

You are just

"You" refers to God. (See: rc://en/ta/man/translate/figs-you)

the one who is and who was

See how you translated a similar phrase in Revelation 1:4.

they poured out the blood of your saints and prophets

AT: "evil people murdered the saints and prophets." (See: rc://en/ta/man/translate/figs-metaphor)

you have given them blood to drink

God will make the evil people drink the waters that he turned to blood.

I heard the altar reply

Possible meanings are 1) "I heard the angel near the altar say" or 2) "I heard the souls of the saints under the altar say" (See: rc://en/ta/man/translate/figs-metonymy)