That's not true. Matthew 5:48
"Be perfect, therefore, as your heavenly Father is perfect." God is telling folks here that they can use the gift of reason that was given in Gen 1. Nothing had ever changed since man was created in the image and likeness of God.
Matthew 5:33-48
33. "Again, you have heard that it was said to the people long ago, `Do not break your oath, but keep the oaths you have made to the Lord.'
34. But I tell you, Do not swear at all: either by heaven, for it is God's throne;
35. or by the earth, for it is his footstool; or by Jerusalem, for it is the city of the Great King.
36. And do not swear by your head, for you cannot make even one hair white or black.
37. Simply let your `Yes' be `Yes,' and your `No,' `No'; anything beyond this comes from the evil one.
38. "You have heard that it was said, `Eye for eye, and tooth for tooth.'
39. But I tell you, Do not resist an evil person. If someone strikes you on the right cheek, turn to him the other also.
40. And if someone wants to sue you and take your tunic, let him have your cloak as well.
41. If someone forces you to go one mile, go with him two miles.
42. Give to the one who asks you, and do not turn away from the one who wants to borrow from you.
43. "You have heard that it was said, `Love your neighbor and hate your enemy.'
44. But I tell you: Love your enemies and pray for those who persecute you,
45. that you may be sons of your Father in heaven. He causes his sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous.
46. If you love those who love you, what reward will you get? Are not even the tax collectors doing that?
47. And if you greet only your brothers, what are you doing more than others? Do not even pagans do that?
48. Be perfect, therefore, as your heavenly Father is perfect.