What did the Jerusalem church do and write when they sent Paul and Barnabas back to Antioch?

Les explains that it pleased the apostles and elders, with the whole church at Jerusalem, to send chosen men of their own company to Antioch with Paul and Barnabas. They wrote letters after this manner, confirming the decision in writing, and no doubt signed it, that they were no longer going to force Gentile converts to keep the Law, practice circumcision, and so forth. Dropping down to verse 29, the Holy Spirit repeats that this was part of the written agreement sent from the Jerusalem church to Antioch: that they abstain from meat offered to idols, and from blood, and things strangled, and from fornication; if they keep themselves from these, they shall do well. Les connects these instructions back to Leviticus 17 and 18, noting that even though they were part of the Law, God could sanction their continuing alongside the Gospel of Grace. He firmly believes that while believers are under Grace, not Law, God still holds them accountable for not doing these things. He also observes that Satan worship often begins here, with drinking blood, becoming immoral, and similar practices.