What Is Eid-al-Ghadir and Why Do Shia Muslims Celebrate It?

“Oh Allah, bear witness. ‘Oh people, Allah is my Lord and I am the lord (leader) of the believers. I am worthier of believers than themselves. Of whomsoever I had been Master (Mawla), Ali here is to be his Master (Mawla). Oh Allah, be a supporter of whoever supports him (Ali) and an enemy of whoever opposes him (Ali).”