John Lightfoot on Luke 16:26

[A great gulf fixed.] It is well known from the poets, that inferi among the Latins comprehend the seat both of the blessed and the damned, denoting in general the state of the dead, be they according to the quality of their persons allotted either to joys or punishments. On this hand, Elysium for the good; on that hand, Tartarus for the wicked; the river Cocytus, or Acheron, or some such great gulf fixed betwixt them. The Jews seem not to have been very distant from this apprehension of things. "God hath set the one against the other, that is, hell and paradise. How far are they distant? A handbreadth. R. Jochanan saith, A wall is between." But the Rabbins say, They are so even with one another, that you may see out of one into the other.

That of seeing out of the one into the other agrees with the passage before us; nor is it very dissonant that it is said, They are so even with one another; that is, they are so even, that they have a plain view one from the other, nothing being interposed to hinder it, and yet so great a gulf between, that it is impossible to pass the one to the other. That is worth noting, Revelation 14:10, "Shall be tormented with fire and brimstone, in the presence of the holy angels, and in the presence of the Lamb."