Va’eschanan contains, amongst other treasures, the first paragraph of the Shema. In it (6:6) we are commanded that ‘these words that I command you shall be on your hearts’ (al levavecha); a phrase on which the Sfas Emes asks a cracker of a question and volleys back a classic answer.
Why does Moshe tell us that these words should reside on our hearts – surely the more appropriate home for them should be in our hearts, representing our having fully internalised and worked upon these words and concepts.
How are we to understand this command of on your hearts?
The Sfas Emes answers that for sure the best place for these crucial words is in our hearts, for the reasons outlined above. But Moshe is telling us that if we are not on the level that these words can make it into our hearts and really become part of us, then at least they should remain floating and hovering above our hearts as opposed to being rejected and repelled completely.
That way when the time comes that we can find room for these words and concepts in our heart, they will simply seep in naturally; for they have always been there or thereabouts waiting to come into our hearts.