The eye is the messenger of the heart.

Come, fair repentance, daughter of the skies!
Soft harbinger of soon returning virtue!
The weeping messenger of grace from heaven! [ Brown ]

A wanton eye is a messenger of an unchaste heart. [ St. Augustine ]

Where the devil cannot come, he will send his messenger. [ German Proverb ]

Stay till the lane messenger come, if you will know the truth of the thing. [ English Proverb, collected by George Herbert ]

Troubled blood through his pale face was seen to come and go, with tidings from his heart, as it a running messenger had been. [ Spenser ]

A babe in a house is a well-spring of pleasure, a messenger of peace and love, a resting-place for innocence on earth, a link between angels and men. [ Tupper ]

A prolific source of obscurity is ambiguous arrangement. A member of the Savage Club, so runs the story, was one day standing on the steps of the club house. A messenger stopped and inquired: Does a gentleman belong to your club with one eye named Walker? I don't know, was the answer, what was the name of his other eye? [ Sir J. F. Stephen, The Art of Authorship, 1891 ]

As well might a lovely woman look daily in her mirror, yet not be aware of her beauty, as a great soul be unconscious of the powers with which Heaven has gifted him; not so much for himself, as to enlighten others - a messenger from God Himself, with a high and glorious mission to perform. Woe unto him who abuses that mission! [ Chambers ]