Aitareya Āraṇyaka 1.3.6

1.3.6

tad iti pratipadyate.
tat tad iti vā annam.
annam eva tad abhiprati/padyate \
etāṃ vāva prajāpatiḥ prathamāṃ vācaṃ vyāharad ekākṣara/dvyakṣarāṃ tateti tāteti \
tathaivaitat kumāraḥ prathamavādī vācaṃ vyāharaty ekākṣaradvyakṣarāṃ tateti tāteti \
tayaiva tat tatavatyā vācā pratipadyate \
tad uktam ṛṣiṇā.
bṛhaspate prathamaṃ vāco agram (RV X 71,1a) ity.
e/tad dhy eva prathamaṃ vāco agram \
yat prairata nāmadheyaṃ dadhānā (RV X 71,1b) iti.
vācā hi nāmadheyāni dhīyante \
yad eṣāṃ śreṣṭhaṃ yad aripram āsī/d (RV X 71,1c) ity.
etad dhy eva śreṣṭham etad aripram \
preṇā tad eṣāṃ nihitaṃ guhāvir (RV X 71,1d) i/ti-.
-idam u ha guhādhyātmam.
imā devatā.
ada u āvir adhidaivatam.
ity e/tat tad uktaṃ bhavati \\ 6 \\

This is an exact repetition of the third khanda. According to the commentator, the third khanda was intended for the glory of the first word tad, while the sixth is intended for the glory of the whole hymn.