Not what goes into the mouth defiles a man; but what comes out of the mouth [words], this defiles a man. (Mt 15:11 NKJV – parenthesized word added)
But those things which proceed out of the mouth come from the heart, and they defile a man. (Mt 15:18)
If anyone defiles the temple of God, God will destroy him. For the temple of God is holy, which temple you are. (1 Cor 3:17)
The definition of defile is: spoil, sully, impair, debase, or degrade; to desecrate or profane something sacred. The words that come out of our mouths are capable of defiling us!
From the verses quoted above, we understand that our words can displease God, because we are His holy, sacred temple. He never wants us to speak words which would degrade us. Words are the heart’s reaction or response to people or circumstances. He wants us to respond to all things as He would—with love and mercy.
Jesus is our example in all things. (1 Pet 2:21-24; Jo 13:13-16) He has called us to follow Him, as He leads and shepherds us.
A good man out of the good treasure of his heart bringeth forth that which is good . . . (Lk 6:45a KJV) Let us encourage ourselves to speak forth only words which are good and edifying—which bring glory to God and blessings to mankind.