One of the features of Buddhism is that it has no central authority. The Buddhist advised his disciples in the Maha-Parinibbana Sutta (DN 16 of the Pali Canon):
Then the Blessed One said to Ven. Ananda, “Now, if it occurs to any of you — ‘The teaching has lost its authority; we are without a Teacher’ — do not view it in that way. Whatever Dhamma & Vinaya I have pointed out & formulated for you, that will be your Teacher when I am gone. (trans. Ven Thanissaro Bhikkhu)
However, over countless generations, across many parts of the Buddhist world, this has led to a lot of question and discussion about what is the highest and most important of the Buddha’s teachings?
Countless priests and teachers have tried organizing the jumbled mess of disparate Buddhist teachings and sutras that comprise the corpus of Buddhism into a hierarchy. Inevitably there is some teaching at the top that is the highest teaching with other texts and teachings complementing or leading up to it.
Many Buddhist schools even today are basically built around one hierarchy or another. Then there is the anti-intellectual strain that tries to throw it all away claiming “fingers pointing at the moon”.
So how does one make sense of all this? Which one is the highest teaching?
I tend to take the practical approach and say that whichever teaching or sutra is the most meaningful for you is the one you should treat as the highest teaching. I don’t mean this as an “anything goes” approach, but rather the one the inspires and benefits you the most and keeps you motivated to follow and practice the Buddhist teachings.
This utilitarian approach runs against the more theoretical arguments of Buddhists past and present but I don’t really care. If a teaching is touted as the best and most important in Buddhism, but has no resonance or is incomprehensible, what use is it to you?
Further, your outlook will change and evolve as your understanding of Buddhism also deepens so what seems like the best and most useful sutra to you will change. In my younger years, I was really fixated on the Heart Sutra, then later the Amitabha Sutra (a.k.a. The smaller Sukhavati Vyuha Sutra), and these days it’s a mix of the Lotus Sutra and the Diamond Sutra. And it may change again.
That’s normal and nothing to be ashamed of. The point is, don’t stop moving forward. Always be growing, learning and maturing as a person until the very end.