Where is the first instance of the cup and broken bread in the Bible?
The first instance of the cup and broken bread is the Lord's upper room experience. This is where the practice of communion began, as referenced in 1 Corinthians 10:16-17 concerning the cup of blessing and the bread we break, which speak of the Lord's table.
Les explains that in 1 Corinthians 10, Paul shifts gears from discussing resisting temptations and fleeing idolatry to the Lord's communion table. Paul writes in verse 16 about the cup of blessing which we bless, the communion of the blood of Christ, and in verse 17 about the bread which we break, the communion of the body of Christ. Les then asks where the first instance of presenting the cup and the broken bread is, and answers that it is the Lord's upper room experience. So the first occurrence of the cup and broken bread in Scripture is that upper room event, which established the practice of the Lord's table.