"I tell you this, you must give an account on judgment day for every idle word you speak. The words you say will either acquit you or condemn you." Jesus (The Bible, Matthew 12:36-37, New Living Translation).
What does Jesus mean when he says we must give an account for every idle word we speak on judgment day? What are idle words?
Well, in the context, Jesus had just cast demons out of a man that made him unable to see or talk. And the religious leaders of that day (the Pharisees) said Jesus was able to cast the demons out by the power of Satan, not the power of God or the Holy Spirit. Their accusation was careless and thoughtless. Worse, their words of condemnation for Jesus and his work were slanderous and abusive.
So, Jesus takes issue with them, and among other things, tells them that they would have to give an account for every idle word they spoke. In the context, then,"idle words" are careless, abusive, slanderous words spoken about Jesus or his work.
Today, people speak such words all the time. In movies and tv shows, celebrities carelessly speak Jesus' name as a curse word. Politicians and other leaders put his name down and ridicule his followers in the name of plurality. At work, people disrespect his name and his word with sarcastic responses every time anyone speaks of them. Over and over in many situations every single day, people speak idly, carelessly & abusively about Jesus.
One guy I know constantly mocks the name of Jesus and the Bible and the church almost every time I see him in the fitness center where I work out. It's an obsession for him. He sees me, makes a beeline for me, and begins to mock or make sarcastic statements about Jesus or the Bible or church or all three.
One day he will give an account. One day EVERYONE who speaks such careless or thoughtless or disrespectful and abusive words about Jesus or his work or people will give an account. And their words will either acquit or condemn them.
So, speak the name of Jesus carefully. Speak it in praise and thanksgiving. Speak about his work and words and people with respect. Or don't speak it at all.