6 Answers

Because Satan walks the earth to and fro seeking to kill and destroy and he has a lot of people that are way too willing to help him.

we become the product of our environment, an evil thought can not reside with that which is pure.

Because Satan roams the earth.But his day's are numbered.

I think you would have to first ask the question: What is evil? I understand evil as the antithesis of Good. In other words evil is good that has been distorted or twisted. Good can exist without evil but evil canNOT exist without good. For example murder is evil. However, in order for murder to take place a person must be first exist (which is good). Or when 2 people are in love...and they are willing the good for the other...no evil needed for the Good that is occurring.

I guess what i am trying to say is we do not have to have evil for the sake of evil. But perhaps it is just an unfortunate consequence of the free will God has given us. As God has called us to love him...freedom is needed in order to make that choice. If we did not have free will we would be slaves, and therefore unable to love.

Two people have given truthful and serious answers.

Here is another:

(Revelation 12:12) . . .Woe for the earth and for the sea, because the Devil has come down to YOU, having great anger, knowing he has a short period of time.”

It is true, we are living in the foretold age of destruction and it is reaching a climax.
It is also described as the 'last Days' ---'the conclusion of the system of things'--- 'the time of the end'

Gods invisible enemy rules the earth and has messed up the governments and the banks but not half as much as he has messed up the religions of this world see 2 Cor 4v4

Because for their to be good there has to be evil, good need's something to conquer, just as i believe in god unfortunately i believe in the devil too.