Therefore you shall be perfect, just as your Father in heaven is perfect. (Matthew 5:48)
Brethren, do not be children in understanding; however, in malice be babes, but in understanding be mature (teleios). (1 Corinthians 14:20)
This passage illustrate teleios in a contrast as teleios is (mature) contrasted with children. Spiritual maturity verses immaturity is presented as a choice. When it comes to understanding the things of the Spirit we are encouraged to be mature as opposed to immature children. Clearly there is a choice to be made on our part. What choice will you make? Embrace the process and grow forward in Christ.