Here are some good quotes on growing in Christlikeness – something we must do and something Christ does in us:

What we think about when we are free to think about what we will –
that is what we are or will soon become.
— A.W. Tozer

Christlikeness is born in us when we deny ourselves in the small tasks of life.
– Gary Thomas

The tapestry of Christlikeness is laid down stitch by single stitch, as God weaves events, attitudes, relationships, and personal affliction through our daily experience.
– Gary Thomas

Life is an incremental series of becoming what you are, in Christ.
– John Piper