WAILING AND GRINDING OF TEETH
The Bible uses this phrase multiple times. Wicked persons gnash their teeth against the righteous to express their hatred or anger as they did at the trial of Saint Stephen (Acts 7:54). Psalm 37:12 states: “The wicked plot against the righteous and gnash their teeth at them.”
Jesus used this phrase as a part of the last judgement. “That is how it will be at the end of time; the angels will go out to separate the wicked from the just and throw them into the blazing furnace, where there will be weeping and gnashing of teeth” (Mt 13:49-50).
The grinding of teeth, along with wailing, expresses great and lasting anguish at the loss of everlasting life in heaven. It also would be their expression of disagreement in seeing others, like the Gentiles and former sinners, enjoying eternal reward with the forefathers Abraham, Isaac, and Jacob (Lk 13:28).
There are baptized Christians who are stuck with the achievements of this world and ignore the life after death. Jesus said, “Everyone who acknowledges me before others I will acknowledge before my heavenly Father. But whoever denies me before others, I will deny before my heavenly Father” (Mt 10:32-33). Let us be in the safe side by acknowledging Jesus as our Messiah.