In Samadhi, knowledge is called "filled with truth".

Verse 47

निर्विचारवैशारद्येऽध्यात्मप्रसादः ॥४७॥

nirvicāra-vaiśāradye-'dhyātma-prasādaḥ ॥47॥

In reaching nirvichara samadhi the mind becomes pure, the Chitta becomes firmly fixed.

Verse 48

ऋतंभरा तत्र प्रज्ञा ॥४८॥

r̥taṁbharā tatra prajñā ॥48॥

In that samadhi, knowledge is called "filled with truth".

When intelligence and consciousness, the essence of Jiva, remain nonreflective, profound and unconditioned, the body, the organs of action, the senses of perception, the mind, intelligence and consciousness - are illumined. 

Knowledge and understanding of the real state of the Atman manifest in luminosity.

When consciousness dwells in wisdom, a truth-bearing state of direct spiritual perception dawns.

This earned spiritual illumination is filled with unalloyed wisdom, glowing

with truth and reality.

This luminosity of the Atman manifests, shining with full fragrance.

Ritambara Prajna is a wisdom which is beyond the sense organs, mind and intellect. Can acquire this Prajna only through yoga sadhana.

Devoid of veiling contamination of any impurites of Rajas and tamas, the mind which is still, like a ripple less water reflects the atman thereby revealing it's true nature that is light of knowledge which can distinguish atman and anatman. It's a progressively clearer stage.

The vidhya which appears in the clearness of mind in this stage of Samadhi, it brings truth alone and there is no trace of avidhya, which is born out of discrimination. The first is, to follow the instructions of the scriptures and the teachers; the second is mainly concerned with removing, by reason (yukti) and inference, objections to the authoritative teaching which is being studied, and so rightly establishing it; but the third is eagerness for constant practice of meditation on what has thus been established by the scriptures and by inferences from them. Perfecting his knowledge in these three ways, the yogin attains yoga.

PATANJALI YOGA SUTRAS,