ISB ~ Revelation 21 v6

the Alpha … the Omega:God created all things in the beginning, and he calls them back to himself in the end. See note on Rev 1:8.

the water of life:The supernatural life of the Spirit (Jn 4:14; 7:37-39; 1 Cor 12:13). Note the contrast with Rev 21:8—here the saints are refreshed with living water; there the wicked are scorched with deadly fire (CCC 694).