Paul, in 1 Corinthians 1:18, writes about “the message of the cross.”
To Paul, the message of the cross was the gospel (1 Corinthians 1:17).
The message of the cross, the gospel, is powerful...it is the power and wisdom of God (1 Corinthians 1:17-18).
It is the message Paul was sent by Jesus to proclaim (1 Corinthians 1:17).
The context of 1 Corinthians 1:17 was that believers in Corinth where boasting about and aligning themselves with certain teachers (1 Corinthians 1:12).
Consequently, they were arguing with one another about which teacher was the best communicator (1 Corinthians 1:10-11).