Sustained love gives people the spiritual light, which provides access to information that is previously unavailable...

To those with less light (in consciousness) through being less loving in their affairs.

And so, even those with great minds are locked out of this higher knowledge, unless they engage the heart!

This is the inbuilt safe mechanism of the Lord.

For a developed mind without a correspondingly developed heart is a danger to both itself and others, as the tempering of the mental nature does not occur as is desirable in a balanced development of character.