According to the accounts of the events that took place on the mountain of transfiguration, which are written in all the Synoptic Gospels, Jesus spoke to Moses and Elijah about his impending death in Jerusalem. In other words, the Lord talked with Elijah and Moses about the suffering and death of the Cross that He was about to face (Luke 9:30-31). 

We can see that the ministry of Elijah, who had tried hard to turn around the depraved hearts of the people of Israel, was completed with the ministry of John the Baptist in New Testament times. After baptizing Jesus Christ to pass all the sins of the world onto Him once and for all, John the Baptist completed his work as a messenger of God and returned to Him (Matthew 3:13-17; 11:14; 17:12; Mark 9:12). 

The Old and New Testaments both testify that John the Baptist fulfilled the same ministry as that of Elijah. The Truth of the baptism Jesus received from John the Baptist is the completion of salvation fulfilled by the righteousness of God.

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