Jane Eyre and the new testament parable of the mustard seed

Editors of Jane Eyre have glossed the term 'mustard-seed' - an endearment used by Rochester to describe Jane after she has agreed to marry him - as a reference to Shakespeare's fairy in A Midsummer Night's Dream. I argue that the term also alludes to the Parable of the Mustard Seed, which appears three times in the New Testament and which Charlotte Brontë undoubtedly knew. The metaphoric language describing the Kingdom of God in the parable provides an important subtext to the theme of moral redemption and to the recurring bird and tree imagery in Jane Eyre.