jñānena tu tadajñānaṃ yeṣāṃ nāśitamātmanaḥ |teṣāmādityavajjñānaṃ prakāśayati tatparam ||
But for those in whom that ignorance of the self has been destroyed by knowledge, that knowledge lights up the Supreme, like the sun.
Explanation
Krishna has just said that knowledge (jñāna) is covered by ignorance (ajñāna), which confuses living beings. Here he says that when this ignorance about the self is removed by knowledge, that knowledge reveals the highest reality, as the sun lights up everything. Traditions differ on what "the Supreme" (param) means: Advaita readings take it as the one Self or Brahman, while devotional readings take it as the Lord.