Go; behold, I send you out as lambs in the midst of wolves.
I remember growing up as a kid without a care in the world; going out to play with friends and coming home exhausted to a nice, warm, home filled with home cooked meals and clean linens. Those were the best days of my life; until my first encounter with evil. After that, I developed an instinct for where and when evil might possibly show itself and I became more aware of what the circumstances were around me.
Even though our parents warned us to stay away from certain things and certain people, knowing that there is potential danger in the world, it all appeared so innocent and care-free. It didn't seem like any harm would come our way, so we paid little attention to their warning. Unfortunately, we sometimes learned the hard way that there's more to life than what meets the eye.
Just like our parents tried to warn us, our heavenly Father implores us to be aware of evil, "Do not enter the path of the wicked and do not proceed in the way of evil men. Avoid it, do not pass by it; turn away from it and pass on. For they cannot sleep unless they do evil; and they are robbed of sleep unless they make someone stumble." Proverbs 4:14-16
Who do you think the "they" are that God refers to in the passage above...in Matthew 7:34-35, Jesus admonishes the evildoers by saying to them, "You brood of vipers, how can you, being evil, speak what is good? For the mouth speaks out of that which fills the heart. The good man brings out of his good treasure what is good; and the evil man brings out of his evil treasure what is evil."
This world is filled with good and evil and it takes a discerning eye and ear to know what is good and what is evil. Many will tell you that it is only one person's opinion what good is and what evil is, but we have the Word of God and the Holy Spirit to help us know what good and evil truly is.
In 2 Timothy 3:2-4 we are told that evil people "will be lovers of self, lovers of money, boastful, arrogant, revilers, disobedient to parents, ungrateful, unholy, unloving, irreconcilable, malicious gossips, without self-control, brutal haters of good, treacherous, reckless, conceited, lovers of pleasure rather than lovers of God."
Jesus tells us that "A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit." Matthew 7:18 So how do we tell which is a good tree and which is a bad tree. Galatians 5:22-23 describes the fruit that comes from the good tree, "is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control."
It seems that in the present day, we would be wise to open our eyes and ears to see and hear what is evil and what is good; not to follow those who appear to be good, without discernment. God is willing and able to help us know what is true and what is not, we need to listen to Him and follow His lead.
God calls us to, "Abide in Me and I in you. As the branch cannot bear fruit of itself unless it abides in the vine, so neither can you unless you abide in Me. I am the vine, you are the branches; he who abides in Me and I in him, he bears much fruit, for apart from Me you can do nothing.
Every tree that does not bear good fruit is cut down and thrown into the fire.