Throwing the Pebbles

For this, throwing the pebbles to stone Satan is a sign of following the act of Prophet Abraham, peace and blessing be upon him, and a way to degrade and humiliate Satan and show him that he is unable to misguide the pilgrim or drag him into the hole of sinning.
No doubt, all these are great pieces of wisdom meant for people who have sound understanding.

clipped from www.islamonline.net Throwing the Pebbles Throwing the pebbles is meant for stoning Satan, may Allah curse him. The pilgrims return to Mina on the 10th, and throw seven pebbles at a stone pillar that represents the devil. This symbolizes Ibrahim’s (Abraham) throwing stones at Satan when he tried to dissuade him from sacrificing his son, Isma`il. Then the pilgrims sacrifice a sheep, reminiscing the story of Ibrahim, who, in place of his son, sacrificed a sheep that Allah had provided as a substitute. The devil is a real malicious enemy to mankind in general and Muslims in particular; he wants to fetter and chain them with sins and disobedience and to do what may invalidate their pilgrimage through whispering to them as he tried to whisper to Prophet Abraham (Ibrahim), peace and blessing be upon him. Satan does this only out of his anger and dissatisfaction of the mercies being showered on the pilgrims on that solemn occasion.