While reading article 1 from Official Constitution Of India, I have not found any such sentence as 'Union of India' thought 'territory of India' word is there, but still in most of the books(like Introduction to the Constitution of India by Durga Das Basu) we come across this line which lays emphasis that " 'Union of India' should be distinguished from the expression 'territory of India' " (Chapter 6 Territory Of The Union)
Later I found 'Union of India' in article 300. Which discusses about Suits & Proceedings and says 300. (1) The Government of India may sue or be sued by the name of the Union of India...
I wish to know what is genesis of that emphasising statement (is there any case of Supreme Court? or Constituent Assembly Debate which talks about that). Is there any real utility in practice of that statement in present time?
I know this much that 'Union' word signifies that there is a federation and federation word itself implies sharing of power between Union and State & who is not part of 'Union of States' (like Union Territory) they can not question the union or ask for sharing the power. But again in Article 239 it's mentioned that Parliament can by law share the power with UT. So what's the significance of that phrase in real practice which i pointed out in the first place ? What difference will it make if books do not contain that line - " 'Union of India' should be distinguished from expression 'territory of India' ".
In short my question is somewhat similar to (but not exactly) that why 'Union of India' is only Union of States and UT are not covered in that statement. At the end we are giving similar treatment to few UTs like Delhi & Pondicherry (i.e Sharing power with them) at par with states. Then why to exclude them from that collective word 'Union of India'. Is there any practical significance of doing that?. Can one give hypothetical example?