The rally is said to be attended by both the moderate and extremist sections of Pakistan's muslim community.
Salman Taseer, was killed in Islamabad by one of his own bodyguards named Malik Mumtaz Hussain Qadri. And in a demonstration of how radicalised the pakistani society has become, there is support pouring in for the assasin who has become a hero of sorts. Last week during his trial in the court he was showered with flowers by the lawyers and many in the crowd patted his back.
The blasphemy law in Pakistan considers any insult to Islam as a capital offence and observers point to its indiscrimanate use in suppressing minority religions.
In 2010, a christian woman called Aasia Biwi was sentenced to death for alleged comments against Islam during a brawl with other farmers. Taseer, who was also reportedly married to an Indian journalist Tavleen Singh and had a son Aatish Taseer, supported the woman.
Taseer's move enraged many and leading religious groups denounced him as an "apostate" and burn his effigies during a nationwide strike recently.
The rally shows off the ugly truth of increasing religious intolerance in Pakistan and that the democratically elected government has been reduced to a mere spectator is worrying the US and other Western countries.