Therefore you shall be perfect, just as your Father in heaven is perfect. (Matthew 5:48)
William Burkitton on this verse:
That is, aim at perfection in all Christian virtues and divine graces, but particularly in this of love, in imitation of your heavenly Father, who is the perfect pattern of all desirable goodness and adorable perfections. To be perfect, as our heavenly Father is perfect, is indeed impossible, as to equality, but not as to imitation. Learn, 1. That there is no standing still in religion; he that will be saved must press on towards perfection. Learn, 2. That no less than perfect and complete perfection in grace, and particularly in the grace of love and charity, is and ought to be the aim of every Christian in this life, and shall be his attainment in the next.
We are given very helpful ideas to implement in our development of Christian character and the life that is kingdom-focused and led by the Holy Spirit in the quote above:
Aim at perfection: our desire should be to become like Jesus, and we are given the example of Jesus in the Sermon on the Mount. Perfection of the standard is given to use in the Sermon and perfection in life was lived before men in the incarnate Christ. Pray to be perfected, day by day as you walk behind Jesus, living the example He gave and spoke. We have the goal before us; let us go after it through leaving the self-life behind and living the Spirit-life.
Particularly in love: The Sermon lived out is a life of love. Love your enemies, love your enemies, and love your God. A life not lived in love is a life out of Christian character. Every act is to be motivated by love. To be like Jesus is to love as He did: lay your life down for others, in love.
Impossible, as to equality, but not to imitation: do not get preoccupied with being sinless because it cannot be done. Rather live to sin less and grow into the image of Christ our example. Growth is a process and is a lifetime achievement.
The two learning points given in the quote are to be prayed over and to meditate on, to chew for a period of time until accepted. Then the teleios process can begin.