Put it in context and the meaning becomes clear.What do you make of Jesus' statement from Matthew 5:48?
"Be ye therefore perfect, even as your Father which is in heaven is perfect."
Matthew 5:43-48 KJV
43) Ye have heard that it hath been said, Thou shalt love thy neighbour, and hate thine enemy.
44) But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you;
45) That ye may be the children of your Father which is in heaven: for he maketh his sun to rise on the evil and on the good, and sendeth rain on the just and on the unjust.
46) For if ye love them which love you, what reward have ye? do not even the publicans the same?
47) And if ye salute your brethren only, what do ye more than others? do not even the publicans so?
48) Be ye therefore perfect, even as your Father which is in heaven is perfect.
"Perfect" here does not refer specifically to moral excellence, rather, complete, mature, consumate, like that.
The theme is Love. Don't just love those who love you, love those who don't, as does God. He cares for the needs of his enemies. So you also be - mature, complete - perfect as your Father in heaven. Don't parse your love, give it to all, like our Father does.
Much love!