Jesus never said anything, even after he rose from the dead, that the Law is now optional for any of them (Matthew 28:20).
Did you miss Jesus explaining that He fulfilled the law, became the Lord of the Sabbath, and taught His disciples that He was instituting two love commandments that encapsulated all of the law and the prophets?
So if obedience to the Law was required to enter the kingdom before the cross, it continue to be required after the cross.
Not in the way you mean it. Several passages of Scripture clearly establish that the coming of Christ has brought an end to the Mosaic Law.
Romans 10:4, “Christ is the end of the law for righteousness to everyone who believes.”
Christ fulfilled the Ten Commandments by living a perfect and sinless life and so when man trusts in Christ as his Savior, Christ’s righteousness is imputed to that individual so we have justification (Romans 4) resulting in the fact that the Law can’t condemn us (Romans
4:4-8; 5:1, 7:1-6, 8:1).
Christ fulfilled the ceremonial ordinances, the shadows and types of His person and work, by dying on the cross for us and in our place.
Christ also fulfilled the Social Law, but now He replaces it with a new way of life fitting to our new salvation.
The believer now is under God’s new law, the law of the Spirit of life in Christ Jesus (
Romans 8:2-4).
Therefore, the doctrine of justification by means of faith in Jesus Christ upholds the Law for three reasons:
(1) Jesus Christ’s death on the Cross satisfied the demands of God’s Law that required that human sin be judged (
Romans 3:26).
(2) Jesus Christ’s death on the Cross establishes the Law by fulfilling the purpose of the Law in driving men to Jesus Christ as their Savior (
Galatians 3:24).
(3) Jesus Christ’s death on the Cross establishes the Law by providing believers the capacity to obey the Law through the ministry of the Holy Spirit (
Romans 8:3-4).
This is why I have stated in the past that the Holy Spirit gives us the knowledge of sin and the way to repentance since the law is not able to. This is why there is no longer condemnation for those in Christ (
Rom. 8:1).