There is a beautiful description of Krishna: "purāna purusham nava yauvanam ca", most ancient yet ever youthful. Who is Krishna? He says "aham ātmā guḍākeśha sarva-bhūtāśhaya-sthitaḥ" - I am the Self of all beings. So that points to the essential nature of all of us - pure awareness. This awareness is most ancient as it has always been there and yet it is ever new as it doesn't accumulate any knowledge so remains fresh and empty. Since it is ever present, it is only a question of recognition and not attainment.

Upanishad says: "yato vāco nivartante aprāpya manasā saha" - that which cannot be reached by words and attained by mind. The words and the mind are the known and they can never realize that in which they rise and fall. So, just as pure awareness, the teaching that points to it is also most ancient and yet fresh each time it comes from direct seeing and not memory. So the endeavor to study Gita or any such text pointing to the highest wisdom is to approach it with a fresh, empty mind. And see for ourselves the truth of it.