# then I will reject the descendants ... and not bring

"Just as I have established the covenant ... so I will never reject the descendants ... and I will bring". This completes the sentence that began in verse 25. God said this to assure his people.

# I will reverse their captivity

"free them from their captivity" or "free them from those who had captured them"

# show mercy to

See how the words "have compassion on" are translated in Jeremiah 30:18.