In James 3:9-12, it shows us, that we can not be a two sided Christians. Sometimes we say a blessing, and sometimes we say something bad to others. God does not like that.
That is called being a double minded Christian, and the Bible says that a double minded Christian will not receive anything from the Lord.
Jesus said in the book of Revelation, that he wants us to be either cold or hot, and that he does not like us to be in the middle, neither hot, nor cold, but somewhere in the middle. He said that he will spit us out of his mouth, if we are like that.
It does not mean that we will always say 100% what is perfect or good, but it does mean, that God wants us to aim to say the good and blessing things to others, as much as we can. And because we are not perfect, and can not be while here on earth, we can aim towards perfection, even if it is impossible for us to be, all the time.
We can not think that we are Christians, and that we please God, just because we go to church, read our Bible, and talk about spiritual things. That is not enough. What God wants us to do, is to stop talking bad things to others, by his grace and by his Holy Spirit in us, so that he can use us, for his purposes. We can not do it perfectly, but we can try, even if sometimes, we make mistakes.
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