Bhagavad Gita, Chapter 16, Verse 24

So let the Shâstra be your authority in ascertaining what ought to be done and what ought not to be done. Having known what is said in the ordinance of the Shâstra, you should act here.

The chapter closes with a real, practical instruction, use this as your actual reference point.

Krishna doesn't end on vague encouragement, he names scripture directly as the real authority to check actions against. Real guidance is offered as something to actually use, not just admire.