यामिमां पुष्पितां वाचं प्रवदन्त्यविपश्चितः ।
वेदवादरताः पार्थ नान्यदस्तीति वादिनः ।। २-४२ ।।
कामात्मानः स्वर्गपरा जन्मकर्मफलप्रदाम् ।
क्रियाविशेषबहुलां भोगैश्वर्यगतिं प्रति ।। २-४३ ।।
भोगैश्वर्यप्रसक्तानां तयापहृतचेतसाम् ।
व्यवसायात्मिका बुद्धिः समाधौ न विधीयते ।। २-४४ ।।

yām-imāṁ puṣpitāṁ vācaṁ pravadanty-avipaścitaḥ |
veda-vāda-ratāḥ pārtha nānyad-astīti vādinaḥ || 2.42 ||
kāmātmānaḥ svarga-parā janma-karma-phala-pradām |
kriyā-viśeṣa-bahulāṁ bhogaiśvarya-gatiṁ prati || 2.43 ||
bhogaiśvarya-prasaktānāṁ tayāpahṛta-cetasām |
vyavasāyātmikā buddhiḥ samādhau na vidhīyate || 2.44 ||

To make his point clear, Krishna has no qualms in criticizing the Vedic rituals and the emptiness and fallacy of blind ceremonial life (verse. 2.42):

यामिमां पुष्पितां वाचं प्रवदन्त्यविपश्चित: ।

Like the Palasa tree blossoming with beautiful red flowers which are not followed by fruits, the eloquent utterances of Vedas about ritualistic rewards are only flowery, never meant to be fruitful.

Even as a boy, the revolutionary Krishna had contended before his parents in Vrindavan that the worship to Lord Indra, the prime Vedic deity, must stop forthwith. The cowherd community, he argued, should instead owe its allegiance and gratitude to Govardhana mountain and the rivers that flowed from it, because it was these that gave food and support to their cows and themselves. “Why worship the unseen and imagined powers when the evident sources of Nature are right in front? Worship to visible sources of Nature would evoke greater feelings and purpose in our minds,” he firmly held.

So, the more mature criticism of Vedic rituals at an advanced age in the Kurukshetra battlefield is perfectly in order. He points out that it is the greed for bhoga and aisvarya (enjoyment and prosperity) that makes these indiscreet people cling to the flowery promises of Vedas (verse 2.43). Vedas are a source of wisdom. Instead of looking for the ultimate wisdom revealed in them, these deluded people run after the exciting prescriptions. For such people, Krishna says, the Yogabuddhi will not dawn at all (verse 2.44):

By these statements, Krishna clearly emphasizes that the yogabuddhi will be attained not by the strength of any rituals, but by the sincere application of a reflective and evaluative mind alone. For Arjuna, though it was too late by any standard, the enquiring spirit made him a totally different person within hours.

Thus, the dawn of viveka and vairagya will alone help one to take up karmayoga. The karmayogic culture and refinement is contrary to ritualistic ambitions and involvement.

Even today, the widespread appeal and influence of Bhagavad Gita is because it is not related to rituals and ceremonies. Gita’s message is more to the non-religious people, although it is immensely important for the religious people too. Any one at any time can take up spiritual enquiry and thereafter mould his life accordingly. The reading of Gita, rumination on its messages, is itself a preliminary for taking up the saadhana Krishna elucidates. The ritualists too can have their entry into viveka and vairagya by reading Bhagavad Gita or Upanishads and then they can get inspired to take up the path of spiritual seeking.