"The Cup" is a symbol of a person's life filled with various circumstances.

"The Cup of Blessing" is a symbol of the fullness of God's blessings, the discovery to man of the Wisdom of God's Will, His Commandments, the adherence to which gives man the true Good News and leads to Eternal Life.

"The Cup of the Lord" is a symbol of following the Teaching of Jesus Christ about the Will of God.  

"The Cup" is also a symbol of God's punishment - the consequences of man's committed transgressions of God's Will, His Commandments.

Negative Meaning:

"The Cup of the Devil" is a symbol of man's life being filled with opposition to the Will of God, wantonness, lawlessness, sin - everything that is also figuratively expressed by the words "Imp," "Satan," "Devil."