The call for followers of Jesus to make more followers of Jesus (Discipleship) in not an optional idea in Scripture

"What you present as the gospel will determine what you present as discipleship. If you present as the gospel what is essentially a theory of the atonement, and you say, 'If you accept this theory of the atonement, your sins are forgiven, and when you die you will be received into heaven,' there is no basis for discipleship." - Dallas Willard

“‎Those who aren't following Jesus aren't his followers. It's that simple. Followers follow, and those who don't follow aren't followers. To follow Jesus means to follow Jesus into a society where justice rules, where love shapes everything. To follow Jesus means to take up his dream and work for it.” ― Scot McKnight

And Jesus came and said to them, “All authority in heaven and on earth has been given to me. Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age.” - Matthew 28:18-20