Before the Fall, Adam doesn’t operate in terms of conscience but in terms of faith / trust. At his creation he is immediately drawn into covenant relationship with God. As a mature human adult he has the thoughts and words given to him including complex concepts and is therefore able to comprehend the commands to eat and not eat and the warnings of consequence. The command not to eat is a religious test of loyalty, not of morality. The content is not a mockery of man but is empty in a sense.