Quote 1
[Porfiry:] "So I suspect now that Nikolay wants to take his suffering or something of the sort." (6.2.24)
Porfiry thinks that Nikolay is taking the rap for the murders to achieve the kind of suffering only available to the actual murderer. He blames this on Nikolay's religion, which celebrates suffering as a means to access divine love.
Quote 2
[Porfiry:] "I am convinced that you will decide, 'to take your suffering.' You don't believe my words now, but you'll come to it of yourself. For suffering, Rodion Romanovitch, is a great thing." (6.2.69)
Porfiry blames Nikolay's desire to suffer on religious fanaticism. So what is his problem? Legal fanaticism? Doesn't he also sound like an echo of Raskolnikov, and of Sonia? Many of the characters believe that suffering is the chief means for purification.