Midst
The "midst" of something in the Bible represents the thing that is most central and most important to the spiritual state being described, the motivation that drives everything else. In general this will be something we love or feel, because at the core of things we are what we love; our loves define us.
(Notae: Apocalypse Revealed 44, 90, 268; Arcana Coelestia 2252, 2940, 10153, 10365, 10557, 10635, 10641)
Arcana Coelestia #223
223. Since the Lord's face is mercy, peace, and all good, it is clear that He always looks with mercy on anybody, and never turns His face away from anybody. Instead it is man, when governed by evil, who turns away his face, as the Lord has said through Isaiah,
Your iniquities are what separate you from your God, and your sins what cause His face 1 to hide from you. Isaiah 59:2.
V:
1. literally, faces
The same applies in this verse which states that 'they hid themselves from the face of Jehovah because they were naked'.