The court has also directed the Federal Investigation Agency (FIA) to produce evidence against the suspects, who pleaded not guilty.
All the four suspects arrested by the FIA are in jail on judicial remand.
The court also dismissed the bail plea of one of the suspects, a college professor.
Earlier, a Christian man hailing from the Kharian tehsil of Gujarat city in Pakistan was arrested by the police on a blasphemy charge.
He was arrested and moved to another place instead of the lock-up after rumours started to circulate that religious groups intended to attack the police station.
The complaint was filed by Nadeem Ahmed in Dinga town, who said that his friend Ishtiaq Ahmed Jalali had told him that a sweeper working at a private hospital had allegedly uttered provocative remarks about the Holy Prophet.
Nadeem claimed that when he spoke to the sweeper to verify the allegation, the latter repeated the remarks.
The case against the suspect has been registered under Section 295-C (Use of derogatory remarks, etc, in respect of the Holy Prophet) of the Pakistan Penal Code.
The blasphemy law is very contentions in Pakistan with several lawmakers calling for its reform.