What does 1 Chronicles 28:20 mean?

Then David told Solomon, 'Be strong and brave, and get to work. Don’t be afraid or discouraged, because the Lord God, my God, is with you. He won’t leave you or let you down until you finish building the Lord’s house.' 1 Chronicles 28:20 - Modern Text Bible

(David encourages Solomon to be courageous and confident, reminding him that God will be with him through the whole project.)