Here "the face of" someone can be an idiom that refers to the that person's presence. It is sometimes omitted in translation. Alternate translation: "the Lord" (See: [[rc://en/ta/man/jit/figs-idiom]])
"with the same spirit and power that Elijah had." The word "spirit" either refers to God's Holy Spirit or to Elijah's attitude or way of thinking. Make sure that the word "spirit" does not mean ghost or evil spirit.
# turn the hearts of the fathers to the children
"persuade fathers to care about their children again" or "cause fathers to restore their relationships with their children"
The heart is spoken of as if it were something that could be turned to go in a different direction. This refers to changing someone's attitude toward something. (See: [[rc://en/ta/man/jit/figs-metaphor]])
What the people will be prepared to do can be stated clearly. Alternate translation: "make ready for the Lord a people who are prepared to believe his message" (See: [[rc://en/ta/man/jit/figs-explicit]])