There is a reference in the Epistle of St. Paul the Apostle that he received teachings from the Lord
Regarding the Sacrament of the Eucharist, the Apostle says: "For I received from the Lord that which I also delivered to you: that the Lord Jesus on the same night in which He was betrayed took bread" (1Cor.11: 23). Here the Apostle speaks about the entrustment he received from the Lord and which he commanded to the church in Corinth. The Holy Bible does not tell us how and when the Apostle Paul received it from the Lord. He is giving us an idea about the Church dogmas and how they entered the Church through entrustment.