Blessing (berakhah; eulogia): Sometimes means the form of words used in invoking the bestowal of good, as in Deuteronomy 33:1, Joshua 8:34; and James 3:10. Sometimes it means the good or the benefit itself which has been conferred, as in Genesis 27:36, "Hast thou not reserved a blessing for me?" and Proverbs 10:22, "The blessing of Yahweh, it maketh rich." "The cup of blessing" (to poterion tes eulogias, a special use of the word in 1 Corinthians 10:16), means the cup for which we bless God, or which represents to us so much blessin g from God.
James M. Gray