Bhagavad Gita Verse 33, Chapter 4

shreyaandravyamayaadyajnyaanjnyaanayagnaha parantapa |
sarvam karmaakhilam paartha jnyaane parisamaapyate || 33 ||
 
Superior to sacrifice of materials is the sacrifice of knowledge, O scorcher of foes. All actions completely culminate in knowledge, O Paartha.
 
shreyaan : superior
dravyamayaat : material oriented
yajnyaat : sacrifice
jnyaana-yagnaha : knowledge sacrifice
parantapa : O scorcher of foes
sarvam : all
karma : actions
akhilam : completely
paartha : O Paartha
jnyaane : knowledge
parisamaapyate : culminate
 
Having pointed out the defect of finitude in the wide range of yajnyaas, Shri Krishna praises jnyaana yajnya or the sacrifice of knowledge. Another interpretation, but on similar lines, is that the yajnya of knowledge is the only one that leads us to the path of shreyas or bliss, rather than the path of preyas or the pleasant.
 
We learned about the sacrifice of knowledge in an earlier shloka. In this yajnya, we go through three steps to acquire the right understanding and knowledge through study of the scriptures: shravana, manana, nidhidhyaasana. Shravana is listening with complete attention. Manana is deep contemplation on the teachings. Nidhidhyaasana is internalizing the teachings through concentration and meditation.
 
So why is the sacrifice of knowledge better than the other sacrifices? Shri Krishna offers the answer in the second line of the shloka. He says that all actions culminate in knowledge. If we add the context of karmayoga to this sentence, the meaning becomes : all selfishness that motivates actions completely ends in the realization of infinitude. It is like a river that stops flowing when it reaches, or realizes, the ocean.
 
Let's dig into this a little deeper. What does it mean to end selfishness? It means that the notion of doership and enjoyership ends. No more does one think "I am doing this" and "I have obtained the result". Furthermore, this knowledge is permanent. It is not a finite material object like the result of any other yajnya like material yajnya and so on.
 
Therefore, when we truly understand this highest knowledge that everything is the eternal essence, we identify with infinite and permanent, thereby ending our sense of finitude. Once that happens, we continue performing all our actions. However, all selfish motives behind those actions will have completely vanished.