MacBeth is tantalized by the possibility of becoming king. Already the witches’ oracle that he would become the Thane of Cawdor is fulfilled, and that was an impossibility.
So now, the next oracle is bound to happen!
MacBeth, egged on by his power-hungry wife, takes matters into his own hands. He kills the existing king and frames the guards. As MacBeth is the most outstanding Scottish warlord and hero, he is named king.
But then everything begins to spiral downward. He hires some wicked assassins to kill would-be rivals. He hallucinates the ghosts of those he has killed with treachery. His wife goes insane and then dies. The more enemies — real or perceived — he kills, the more they multiply. Does he enjoy even one moment of the power he lusted for?
The witches followed the pattern of the serpent in Eden: You won’t die, Eve. You’ll become like God knowing good and evil. It was a half-truth, and it brought temptation to fruition (sorry, couldn’t resist that pun) and the ultimate demise of humanity.
Modern society is now based on half-truths as the Bible has been discarded and new ideals and new moralities are spreading.