Lamentations (Book)

Could you explain exactly what "lamenting" is and how it applies to the Christian life? Are they complaints before the Lord?

Why does the ESV translate the word "kidneys" instead of "hearts" [Lamentations 3:13].

Do you know anything about the Lost Tribes of Israel (Black Hebrew Israelites)? [Genesis 10, Lamentations 5:10, Song of Solomon 1:6].

I often feel my prayers are so repetitive, that it is almost a mindless regurgitation, how do I remedy that? [Lamentations 3:22-23, Matthew 6:11].

After Isaiah chapter 40, there appears more alignment with the New Testament message, & there may also be a relationship between the 39 chapters of Isaiah to the 39 books of the Old Testament. Do you think that numerology has anything to do with this? [Lamentations, Psalm 119].

Old Testament symbolism is also in the book of Revelation