Adam and Eve were too unintelligent (immature? unwise?) to understand, much like telling a toddler not to eat cookies from the cookie jar on the counter.
This is literally what 'ignorant' means.
I like to... adapt the story, where god is a dog owner, and adam and steve are golden retrievers. It's not Adam and Steve's fault that the human left the squeaky toy out for them to play with... any one older than a toddler is going to realize that, of course, they're going to find it and play with it. they're dogs. it's a squeaky toy. it's meant to be played with. Only an asshole kicks their dogs out because they got into the squeaky toys.
Now, couple that with a being that's supposedly omniscient, all knowing. Of everything- past and future included. If this is all to believed, then it was all god's intent that Adam and Eve eat the damned fruit.
Which means the asshole set them up, just so he could kick them out. And, ultimately, just so he could LARP as a white-knight savior.