There it is. You believe in more than one gospel which explains a lot of why you have no understanding of scripture. There is only one gospel. Teaching any other gospel is forbidden.
2 Corinthians 11:1 But I am afraid that just as Eve was deceived by the serpent’s cunning, your minds may somehow be led astray from your sincere and pure devotion to Christ. 4 For if someone comes to you and preaches a Jesus other than the Jesus we preached, or if you receive a different spirit from the Spirit you received, or a different gospel from the one you accepted, you put up with it easily enough.
Galatians 1:6 I am astonished that you are so quickly deserting the one who called you to live in the grace of Christ and are turning to a different gospel— 7 which is really no gospel at all. Evidently some people are throwing you into confusion and are trying to pervert the gospel of Christ. 8 But even if we or an angel from heaven should preach a gospel other than the one we preached to you, let them be under God’s curse! 9 As we have already said, so now I say again: If anybody is preaching to you a gospel other than what you accepted, let them be under God’s curse!
Any other gospel but the one gospel "is really no gospel at all". In regards to anyone preaching a gospel other than the one gospel "let them be under God's curse!". As Paul said "Evidently some people are throwing you into confusion and are trying to pervert the gospel of Christ".
The new testament is the new covenant. There will be no sacrifices in an imaginary future millennial kingdom because Jesus Christ made animal sacrifices permanently obsolete with His once for all sacrifice. Animal sacrifices were only done for the purpose of foreshadowing Christ's sacrifice (Hebrews 10:1) and would serve no purpose in the future except to be an insult to Christ's once for all sacrifice.