pando, I think mooks should be answering this, but . . . .
I don't think he wants to know the p/w, he wants to validate it; he said:
". . . i want to create a page and allow users to update their password after verification through the database . . "
in which case comparing hashed values will work.
If you connect succesfully with say SQLPlus and walk away from the PC what stops me (apart from geography) from typing ALTER USER ?