Final answer:
The Apostle Paul commended Timothy, an early Christian writer. Polycarp of Smyrna, Ignatius of Antioch, and Papias of Hierapolis were three early church fathers who were pupils of the Apostle John.
Step-by-step explanation:
Early Christian Writer Commended by the Apostle Paul:
The early Christian writer who was commended by the Apostle Paul is Timothy. Paul refers to Timothy as his "true child in the faith" and praises his genuine faith in 2 Timothy 1:5 and 2 Timothy 3:14-15.
Three Early Church Fathers Pupils of the Apostle John:
1. Polycarp of Smyrna: Polycarp was a disciple of the Apostle John and became the bishop of Smyrna. He was highly regarded for his faithfulness and martyrdom.
2. Ignatius of Antioch: Ignatius was also a disciple of the Apostle John and became the bishop of Antioch. He wrote several letters that are important for understanding early Christian beliefs.
3. Papias of Hierapolis: Papias was a student of the Apostle John and wrote a five-volume work called the "Expositions of the Sayings of the Lord," which unfortunately has been lost.
These early church fathers played significant roles in the development of early Christian theology and practices.