Where did the idiom "asking Jesus into your heart" come from? Where did the idea of "asking Jesus into your heart" come from? That figure of speech is not explicitly from the bible or probably even early church history. Can anyone find its first use and maybe why it's become so pervasive?

I'm looking for something like "Pastor John Smith used the saying once at a conference in 1850" or something like that. I can assume that people use the bible to come up with this phrase. I'm wondering more about the historical origin of its usage.
There is a famous painting called "The Light of the World," painted by William Hunt in 1853.  By his own statement, it comes from Revelation 3.20, and represents Jesus knocking at the heart of an obstaninate sinner, on a door with no handles, and which must be opened from the inside.  



The image itself has been copied many times, and this is the version I always think of:



While the context of Revelation 3.20 ("Behold I stand at the Door and Knock") is not about salvation, it is often used in services as an altar call, thus identifying it with "opening your heart to Jesus." Here for example, is a church using that call exactly.