This can be stated actively. Alternate translation: "Though deception covers his hatred" or "Though he covers his hatred with deception" (See: [[rc://en/ta/man/translate/figs-activepassive]])
Keeping people from knowing that he hates them is spoken of as covering his hatred. Alternate translation: "Though he lies to keep people from knowing that he hates them" or "Though he lies so that people will not know that he hates them" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Being exposed represents being discovered or becoming known. Alternate translation: "his wickedness will become known in the assembly" or "the assembly will discover his wickedness" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-activepassive]])