YOU ARE PERFECT, SINCE YOUR FATHER IN HEAVEN IS PERFECT

I will reiterate that I am not a Greek "scholar" but this is what I have been given in my studies for your consideration.  June

Matthew 5:48 "You will be [Greek - esesthe] [are- as His ongoing Work] Perfect since/just as [Greek - osper] your Father in Heaven is Perfect."

This is quite a departure from the daunting sound of command of the traditional translation "BE YE Perfect as your Father in heaven is perfect." that has caused much concern and confusion.  This uses both the legalistic prejudices of the translators and the King James English of the time to give the phrase this "flavor".

As in Matthew 6:9, ("The Lord's Prayer") use of the archaic KJV English hides more powerful and accurate meaning:

The same tense in the "Lord's Prayer" that states "Hallowed (set apart for special use/Unique) be thy name (nature/character/essence)." is used for other phrases that appear to command that He or we "be" something, ["let Your will be done."] rather than that He or we ARE a certain thing: "Your will IS done on earth as it is in heaven.", the scripturally consistent truth.

The KJV translation uses  the English style of the time for the phrases that say "Be ye" which, in modern language means closer to "You are", and "Is".  As in the inappropriate translation of the quotation "Hallowed be Thy name", since there is no question that God's nature (name) IS Unique and "set apart" from that of all created entities, enjoining Him in a prayer to "be" "Holy"/Unique cannot be an accurate translation.  And looking at the other phrases that use the archaic language are also inaccurate and steal both the true meaning and the power in the prayer.

Try reading the "Lord's (Greek: Owner's) Prayer" in this way, and see the power from the original Greek for alternate translation of the words:

Our Father in the heavenlies, Unique/Set Apart is Your Nature/Character/Essence.
Your Kingdom IS Come; Your Will IS Done, on earth as it is in the heavenlies.
You give us this [each] day everything that we need [for our spiritual best].
You let go off /release what we owe to you just as we also have let go off/released what is owed to us.
And do not drag us into being purified [the refiner's fire], but deliver/rescue us from worthlessness/poor quality. 
[not in most older translations: For Yours IS the Kingdom and the Power and the Glory to the Ages. Truth [amene]

So returning to the quotation in Matthew 5:48:

1) Are we "perfect" according to the "Law" (given by God to Moses) which was given to demonstrate through the nation of Israel that "fallen" mankind was incapable of "obedience" and needed a "Savior/Rescuer" and a "new Spiritual birth"? No.

2) Are we "perfect" according to our "fleshly" existence in this world? No

3) Are we "perfect" in this "fleshly" existence as compared to God in His Divine Spiritual existence? No

But are we Perfect as God's handiwork (Isaiah 64:8), at whatever stage in His formation of each of us and in every day and moment of our formation?  YES! 

Because, since He is Perfect, His WORK is Perfect at every moment for His ordained purposes and plan.  And as we ALL are His Handiwork (Isaiah 64:8), we are ALL Perfect in HIS Way.

So in Matthew 5:48, it is not a possibility for us to be "perfect" in any of the evaluations of our "fleshly" status/existence that apply above that received a "No".  But it is consistent and scripturally supported that "We will be/are Perfect (as His Handiwork), just as/since our Father in heave is Perfect."  As His Handiwork is Always, at each moment, Perfect for His ordained purpose and timing with HIM as the "Former" of each "pot".

The Greek word, esesthe in the scripture above: You will be perfect, is more appropriately translated as a statement than as a command and is used in that manner in many other N.T. scriptures.  So, as God's Handiwork, it is a given that we ALL will be perfect, since He ordains and accomplishes all that He desires/wills/wishes. Therefore, at any point in the creation of His Work, it is/we ARE Perfect for each moment in His production/formation of us, of ALL.