The problem is not the animal and the problem is not the songs. Animal sacrifices don't save you and singing nice songs on Sunday doesn't save you. But, a song in faith from the heart God will accept and an animal sacrifice from the heart, God will accept. Singing songs on Sunday by tradition does not praise God if there is no sincerity of heart. Animal sacrifices God despises if there is no sincerity of heart in doing the sacrifice.
Animal sacrifices are commandments in the Torah.
Ezekiel 40-48 describes the Temple of the Messianic Age. Let us continue in Ezekiel 40-48.