If I recall, the apostles suggesting building shelters for them and a voice from heaven interrupted them directing them to listen to Jesus.
Certainly open to interpretation. One such would be that the Old Covenant was over, and the teachings of Moses and Elijah ignored, henceforth. That would be a more logical explanation than yours than yours, although I don't think either one totally defines the episode.
Well, just show us the teaching by the apostles or examples of them communicating with the departed.
I have to disagree with that. Jesus said that until heaven and earth pass away, not the least letter of the Law will pass away.
God's law defines who He is and points to Christ.
Sin is still sin. How it's dealt with has changed and since the perfect sacrifice of Jesus, who the law was foreshadowing, has come, there is no reason for the sacrifices that foreshadowed Him to continue because the blood of bulls and goats could not take away sin.
So we are no longer obligated to live under the old covenant in that regard, but the moral laws have not changed and are not optional. They cannot be ignored.
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But that would be contrary to the word!
Hebrews 4:
[1] Let us therefore fear, lest, a promise being left us of entering into his rest, any of you should seem to come short of it.
[2] For unto us was the gospel preached, as well as unto them: but the word preached did not profit them, not being mixed with faith in them that heard it.
So you see, the difference is not between the OT and NT, but whether one has faith or not.
Yeshua's words in Matthew 5 will not be repealed, Torah is his way as long as the Earth and Heavens remain.
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