The truly good ones are those capable of sin but strive to avoid it, and if they do sin, they repent. Those who don’t understand what evil is aren’t pure they’re just naive. Yes, we are capable of evil, but we choose to do good. This ability to choose allows us to reach higher levels than the angels, who are obligated to do good by their nature. On the other hand, we humans,despite temptation, we consciously avoid evil and pursue righteousness