“Therefore you are to be perfect, as your heavenly Father is perfect.” Matthew 5:48 NASB
Perfect – Yeshua’s demand seems perfectly reasonable, right? You and I can be perfect, can’t we? God demands it. We are accountable. Therefore, we should do it.
When I was much younger, this verse scared me to death. I knew that I wasn’t perfect. I made lots of mistakes. No matter how hard I tried, I always failed. Yet it seems as if “Jesus” was demanding that I never falter. This led me to serious spiritual depression. Knowing that I couldn’t live up to His demand, I either excused my actions or wallowed in guilt. It took a long time to realize that Yeshua wasn’t asking for faultlessness. That is a Greek idea based in a culture that viewed perfection like a mathematical formula. It took a long time to understand that perfection didn’t mean “100% correct.” The Greek verb teleios carries the sense of direction toward completion. That means this verse, in Greek, could be translated, “Be fully complete.” And, of course, no one is fully complete instantly. To be complete, to be fully grown, takes time. It is direction that matters here, not destination, although, of course, the ultimate destination sets the direction. Perhaps the Twelve Step people understand it better. “Progress, not perfection.”
But Yeshua wasn’t speaking Greek. He spoke Hebrew. His implications and references come from the Tanakh, in particular, from Leviticus 19:2. There we discover that the reference is to holiness, not our Greek ideal of perfection. “You shall be holy, for I the LORD your God am holy.” This makes Yeshua’s statement even clearer. Holiness is a matter of setting apart my life for His purposes. Holiness is about submission, about domesticating the yetzer ha’ra, about putting an end to the rebellion. That is also a process. Each day God reveals another way that I can set apart some aspect of my life. Each day I am challenged to be holy as He is holy.
It took a long time to understand this. Then I read this: “The Rabbinic exposition of Leviticus 19 underscores that to be like God, that is, to be holy, means to act in accord with the rules of morality and compassion. One cannot overemphasize that fact, since people do not always correlate ‘holiness’ with morality and ethical conduct in the way in which the Torah insists they are to match.”
I realized that holiness is not simply direction toward the divine. Holiness is living according to the rules God establishes. Holiness is keeping Torah. In most Christian circles, holiness is a collection of good principles and noble actions. But this is not holiness in the Bible. Yeshua knew exactly what He was saying when He drew on Leviticus 19:2. Holiness is living God’s way. Period. Any other way does not meet the biblical definition of holiness. Any other way is my way, no matter how noble or upright it happens to be. Good enough is not holy.
Topical Index: holy, teleios, perfect, good, Torah, Matthew 5:48, Leviticus 19:2
 Jacob Neusner, Judaism When Christianity Began, p. 46.