The letter H involves infinity, because it is only an aspirate. That is why it was added to the names of Abram and Sarai, that each might represent the divine, or Jehovah.

The Hebrew letter "ה" pronounced Hay, begins Psalm 119:33-40. Added to the names Abram and Sarai, it signifies the Infinite and Eternal. (True Christian Religion 272; Doctrine Regarding Sacred Scripture 90)

As Abram represents the Lord, his former quality was to be destroyed; and so the letter H was taken from the name Jehovah, for it is the only one there which involves what is divine, and means I Am, or Esse -- to be; and then he was called Abraham, and Sarai became Sarah. (Arcana Coelestia 2010)

(Odkazy: Apocalypse Explained 38; True Christian Religion 278)