Psalm 4:6 Sacrifices of righteousness

“זִבְחוּ זִבְחֵי צֶדֶק וּבִטְחוּ אֶל יְהֹוָה”

“Offer up sacrifices of righteousness and trust in the Lord.”

“Sacrifices of righteousness” – Commandments of the Lord (Mitzvot), that are considered as offering up a sacrifice.
So, follow his paths and fulfill His laws, even though sometimes involves with.. some self sacrifices. Trust Him, it worth it.

Question: Doesn’t David means real animal sacrifices?

Answer: As explained, the meaning is good deeds. Following G-d’s commandments is considered as a regular animal sacrifice, this equalization is firm: the same way a person gives up his animal in order to make the offering , fulfilling G-d’s will involves overcoming one’s natural desires while doing what is right and good.

Question: Does it mean there shouldn’t be any more animal sacrifices?

Answer: No, Psalm 4:6 doesn’t talk at all about animal offerings. The Psalmist just uses the sacrifices as an allegory for giving up one’s will in order to to fulfill Hashem’s.