Final answer:
The first NT reference of 'ekklesia' is in the Gospel of Matthew. The term refers to a congregation or church, not 'greed.' 'Ekklesia' has a sociological meaning for an officially recognized religion aligned with the state, unlike the U.S.
Step-by-step explanation:
The first New Testament (NT) reference to use the Greek word ekklesia occurs in the Gospel of Matthew. However, there seems to be a slight misunderstanding in the question as 'ekklesia' does not translate to 'greed'. In the context of the New Testament, ekklesia refers to a gathering or an assembly, often associated with a Christian congregation or church. It is critical to distinguish that the term 'greed' is unrelated to 'ekklesia'. The sociological use of the term ecclesia describes an official, nationally recognized religion closely allied with state and secular powers, which does not apply to the United States as it does not have an ecclesia by this standard. If we discuss the concept of wealth and greed in the New Testament, Jesus mentions riches in Matthew 19:24, stating that "It is easier for a camel to go through the eye of a needle, than for a rich man to enter into the kingdom of God".