No, it really isn't. That's what some may say when they are either uneducated or bias against the subject.
Not at all instead that is what some theists say when they have nothing better than to make assumptions about the other person rather than deal with the actual argument.
It's really easy to demonstrate how it isn't cherry-picking. Christians aren't prohibited from eating pork. Right there is a very simple and easily understood example to show that different times are under different standards.
That has nothing to do with contradictions. that is what is called a proscription or in this case not a proscription.
Another simple example, there was no law to follow before the law of Moses was given. Those two examples shows the three different dispensations that have existed.
Dispensations are not contradictions either.
Nor do i accept your claim that there was no law before moses.
A law is knowing the difference between right and wrong
Genesis 2: 16-17. 16 And the Lord God commanded the man, “You are free to eat from any tree in the garden; 17 but you must not eat from the tree of the knowledge of good and evil, for when you eat from it you will certainly die.”
And they must have known that difference and broke a law in doing so.
A law is also knowing what you must or must not do.
Genesis 1: 26. 26 Then God said, “Let us make mankind in our image, in our likeness, so that they may rule over the fish in the sea and the birds in the sky, over the livestock and all the wild animals, and over all the creatures that move along the ground.”
God told them what all men must do.
And if you disagree that these are laws because they were not written down s moses laws were. Paul had something to say on that.
Romans 2:14-15. 14 (Indeed, when Gentiles, who do not have the law, do by nature things required by the law,g they are a law for themselves, even though they do not have the law. 15 They show that the requirements of the law are written on their hearts, their consciences also bearing witness, and their thoughts sometimes accusing them and at other times even defending them.)
But as i said, these are not contradictions that you have given.
A contradiction is something like this.
Genesis 1: 1-27 Where god created all things and then man and woman last.
Where as in genesis 2:5 5 Now no shrub had yet appeared on the earth[a] and no plant had yet sprung up, for the Lord God had not sent rain on the earth and there was no one to work the ground, 6 but streams
came up from the earth and watered the whole surface of the ground. 7 Then the Lord God formed a man[c] from the dust of the ground and breathed into his nostrils the breath of life, and the man became a living being.
two differing accounts make for a contradiction.
