if you look at the ten commandments. 1. I am the Lord thy God, which have brought thee out of the land of Egypt, out of the house of bondage. Thou shalt have no other gods before me.
2. Thou shalt not take the name of the Lord thy God in vain.
3. Thou shalt not make unto thee any graven image, or any likeness of anything that is in heaven above, or that is in the earth beneath, or that is in the water under the earth. Thou shalt not bow down thyself to them, nor serve them.
4. Remember the sabbath day, to keep it holy.
5. Honor thy father and thy mother: that thy days may be long.
6. Thou shalt not kill.
7. Thou shalt not commit adultery.
8. Thou shalt not steal.
9. Thou shalt not bear false witness against thy neighbour.
10. Thou shalt not covet thy neighbor's house, thou shalt not covet thy neighbor's wife, nor his manservant, nor his maidservant, nor his ox, nor his ass, nor anything that is thy neighbor's.
you will see there is no mention of porn

pr0n is not your neighbors wife, not your man/maidservant, ox or ass(iffy on this one)
and adultery.. i don't see people proposing to their pr0no fantasies. theres a difference between lust and adultery. otherwise lust in your heart for anyone other then your wife would send you to hell. hell would be one @#% full place