7 Horcruxes=7 Deadly Sins
Sloth
For all of his talents, Voldemort was sadly lacking in many areas, and his astounding ingorance was one of them. Sloth, a state of carelessness is nowhere more evident than when Voldemort unknowingly misuses one of the Hallows! Thus Sloth is represented by Gaunt's ring.
Envy
As Helena Ravenclaw envied her mother when she stole the diadem, the opposite side of the Ravenclaw Diadem must be envy.
Greed
Since Merope Gaunt was underpaid for Slytherin's Locket, it can be somewhat associated with greed, though other vices are also possible.Â
Wrath
Associated with an act of injury and violence, the boy who lived himself must be the result of Voldemort's Wrath. So yes, Wrath=Harry Potter.
Gluttony
Hufflepuff was the founder associated with making food. By extension, Helga's own cup must be the reverse side of gluttony.
Lust
Generalized to include a strong unnatural desire for a person or an object, it seems clear that Nagini fits the bill on more than one account.
Pride
The cardinal sin of them all. What is more appropriate to associate with it, than Voldemort's desire to replicate and preserve himself in the form of a diary. [Though in truth Voldemort could have been proud of his inheritance, and both Slytherin Locket as well as the Gaunt ring could have suited, if better options were lacking, the diary is the most personal element for Voldemort and thus suits the sin of pride the most].
