In Genesis 26:12, this signifies enriching with celestial good from love, for Jehovah is the very esse of love. (Arcana Coelestia 3406)

In Genesis 1:22, this symbolizes fruitfulness and multiplication. (Arcana Coelestia 43)

3406. 'And Jehovah blessed him' means as regards the good that flows from love within them. This is clear from the meaning of 'being blessed' as being enriched with every celestial and spiritual good, dealt with in 981, 1731, 2846; so that 'being blessed by Jehovah' means being blessed with celestial good that flows from love, for Jehovah is the Being itself (Esse) of love or good, 1735, and therefore the name Jehovah is used when good is the subject but the name God when truth is the subject, 2586, 2769.