The key word in this verse is the word, "so." Peter is saying that in light of what was just previously said, here is how we should respond. He just finished describing how we have been born again by the imperishable seed of the word of God. Because we have been born again in this way we ought to put away all of the things that are part of our old way of living.
This begs the question, "Just how bad were we before we were saved?" Did we really have malice in our hearts? There are many times in the New Testament where the word for malice is used to describe the evil that is within us. The wickedness within us would also include the practice of deceit and hypocrisy and envy and slander. Listen to Paul's words to Titus: