This has to be one of my favourite verses and I know I say that a lot but hear me out. The people had a great celebration because they understood the words that were explained to them. Now, at first, the people mourned and wept because they saw their own sinfulness. They heard the law read to them and found they were not as well off as they had thought. That happens when we have the Word of God. It cuts right to the heart and shows us who we really are. No masks, no hiding, and no trickery. It just cuts, but the same words that break us are meant to heal us.
We too can be sad at times when we find that we do not match up to what we want to be or maybe even should be. But the same Bible that says all have fallen short of the glory of God says that while we were still sinners Christ died for us. You in yourself cannot be good enough but there is one who is. In that we rejoice and in that we celebrate! We look to the cross and rejoice that God loves us that much. That God loves us so much He took our place, He took our shame, and He gave us life. There is so much to celebrate so much love to give and it starts with understanding the word.
In Isaiah 5:11 God says that His word does not return void but it will succeed. In John 1 we read that Jesus is the Word of God. He succeeded. He accomplished His goal. He preached good news to the poor. He has proclaimed freedom to the captives and recovery of sight to the blind, and He set free the oppressed. We should rejoice and have a great celebration because of this. We live because He lives. He has won the grave.
Just a thought,