1. Spiritual identity theft comes in all sorts of subtle ways.
Nebuchadnezzar and Darius never banned Daniel's gang from worshipping Yahweh, except only to bow down to another god in addition to Yahweh. It could be easily done without 'changing' their faith.
2. People are watching.
Your life can be of great interest to non-believers around you. Rulers repeatedly drew spiritual conclusions as they closely observed Daniel's life. You are a representation of God to those who don't know Him.
3. It's OK to be Babylonized.
Daniel was totally immersed in Babylonian education and court life, and was personally promoted by 3 kings. He was a true Babylonian in positions and connections. God interacted with the imperial empires through Daniel.
4. Be set apart while being tactful.
Daniel resolved to not defile himself by remaining pure in faithfulness to God, but also negotiated his way through and grasped opportunities for God's glory to be known.
5. Conviction in youth lays the foundation for later steadfastness.
Daniel was used to drawing boundaries between his faith and the pressures from his surrounding. It's his old habit.
6. Faith is all about living it out.
Daniel never initiated any campaign to 'evangelize' the Babylonians or Persians. Yet his influence changed the hearts of rulers and stood witness to history.
7. It's OK to embrace mysteries and uncertainties!
It's alright to be clueless about what God is doing. Daniel, too, had absolutely no idea even after the visions. But God knew what He's doing.
8. Hope for the future can involve lots of waiting.
Daniel would not see the salvation of his people! 490 years is LOT of waiting! But he had God's presence and that was all he needed.
9. Fear God and you don't need to fear furnace or lions.
Anything can display God's glory, including the enemy's torture and execution tools. It's God who decides when and how.
10. Despite all the above, your prayers still matter to God.
God still hears and answers prayers, often personally with wisdom, guidance and visions.
Can you add to this list when you read the story of Daniel?