In the next verses of 1 John 2, John communicates to whom he is writing. Experiencing Jesus and the subsequent presence of the Holy Spirit caused a fire within him. He had to write about it. Following Jesus is being part of a family developing at individual levels. John wrote to those at all levels of maturity. He wrote for the little children, he wrote for the young men and he also wrote to the Fathers.
Little Children
First he wrote to the little children. Many of the little ones in the faith already knew about God the Father. They knew the stories of Moses, and the songs of the Psalmist. Then Jesus came and opened the way to the Father. Now, they experienced the forgiveness of sins by calling on the name of the Lord Jesus. Doing so, they became little children in the faith.
Young Men
Next he wrote to the young men. By this stage of development, they have learned to overcome the wicked one. They have studied the word of God and it became alive within them. Its truths taught them their identity in Christ and strengthened them to stand against the wicked one. When tempted, the word of God came by the Holy Spirit, and strengthened them against the enemy’s lies.
Fathers
Finally, when he writes to the Fathers, he mentions that they have known the Father not from the beginning but rather, He who was at the beginning. As they have known the Father and experienced not only having their sins forgiven, they have also learned to overcome the wicked one. Eventually they grew into positions of teaching and modeling to others. It resulted from their personal experiences of knowing Him who was the the beginning of the world, coming to know the Son, and their walk with Him through the power of the Holy Spirit.
Don’t let the address to men and Fathers trip you up. The issue is the relationship with God and the level of maturity. Young women and mothers can be used interchangeably. John is writing to all levels of maturity regardless whether male or female, members of the family of God.
John writes for all levels of maturity. He writes for the little children, he writes for the young men and he also writes to the Fathers.