Perhaps another reason for Rochester's envy of Jane's innocence is much like a line from a song: "I wish I didn't know now what I didn't know then." Rochester has suffered much from the deception of his wife and her family who all knew of her dementia before Rochester's marriage. This deception and the burden of being tied to a madwoman certainly bears heavily on Rochester. He would greatly like to be a fresh, innocent young man with out any burdens.
Rochester envies Jane's innocence because it reminds him of what he was like when he was her age. He reminisces, "when I was as old as you, I was a feeling fellow enough...but fortune has knocked me about since...I was your equal at eighteen - quite your equal...nature meant me to be, on the whole, a good man...one of the better kind". Rochester hints that circumstances have caused him to become jaded and depraved, and that now he is little more than "a trite, commonplace sinner".
Rochester also envies Jane's innocence because it manifests itself in a directness and honesty which he finds refreshing. He finds her manner "frank and sincere"; he appreciates that he can be candid with her and receive in return intelligent and truthful responses, unlike "the affectation...coldness...stupid coarse-minded misapprehension of one's meanings (which) are the usual rewards of candour". Rochester is sick to death of phony people with "artificial" values and interests, like his daughter Adele shows signs of becoming with her exhuberant delight in presents and pretty things. Jane, in her innocence, is a welcome diversion from the world in which Rochester lives, and she represents to him a time when he was a better person than he is now (Chapter 14).