We cannot afford to become negligent with our lives due to being familiar with others. Too often after attaining some knowledge about a person, and upon them becoming our co-worker, acquaintance or church family, we let our guard down. Never should we feel the need to stop discerning. People change and not every change is immediately noticeable. When we stop discerning it becomes more difficult for us to detect deceit, betrayal, manipulation, etc. We change, people change, this is life.