Final answer:
Merlin drove Excalibur into the stone to conceal and protect the sword until the rightful king appeared.
Step-by-step explanation:
The story of Merlin and Excalibur
In the legend of King Arthur, Merlin, a powerful wizard, placed the sword Excalibur in a stone as a test to find the rightful king of England. The stone had an enchantment that only the true king could remove the sword. Many tried and failed, but when Arthur, a young boy, pulled Excalibur effortlessly from the stone, it signified that he was destined to be the king.
To drive Excalibur into the stone was Merlin's way of concealing and protecting the sword until the rightful king appeared. It ensured that only the true king, who possessed the qualities needed to rule justly and protect the kingdom, could claim the sword.