In what Pali sutta[s] does the Buddha says something approximately like,
Everyone needs someone better than them, who they can revere and who can guide them: who will be their teacher. But there is no-one better than the Buddha: and so I take the Dhamma as my guide/superior/teacher.
From the Garava Sutta (SN 6.2):
I have heard that on one occasion, when the Blessed One was newly Self-awakened, he was staying at Uruvela on the bank of the Nerañjara River, at the foot of the Goatherd's Banyan Tree. Then, while he was alone and in seclusion, this line of thinking arose in his awareness: "One suffers if dwelling without reverence or deference. Now on what brahman or contemplative can I dwell in dependence, honoring and respecting him?"
Then the thought occurred to him: "It would be for the sake of perfecting an unperfected aggregate of virtue that I would dwell in dependence on another brahman or contemplative, honoring and respecting him. However, in this world with its devas, Maras, & Brahmas, in this generation with its brahmans and contemplatives, its royalty and common-folk, I do not see another brahman or contemplative more consummate in virtue than I, on whom I could dwell in dependence, honoring and respecting him.
"It would be for the sake of perfecting an unperfected aggregate of concentration that I would dwell in dependence on another brahman or contemplative, honoring and respecting him. However, in this world with its devas, Maras, & Brahmas, in this generation with its brahmans and contemplatives, its royalty and common-folk, I do not see another brahman or contemplative more consummate in concentration than I, on whom I could dwell in dependence, honoring and respecting him.
"It would be for the sake of perfecting an unperfected aggregate of discernment that I would dwell in dependence on another brahman or contemplative, honoring and respecting him. However, in this world with its devas, Maras, & Brahmas, in this generation with its brahmans and contemplatives, its royalty and common-folk, I do not see another brahman or contemplative more consummate in discernment than I, on whom I could dwell in dependence, honoring and respecting him.
"It would be for the sake of perfecting an unperfected aggregate of release that I would dwell in dependence on another brahman or contemplative, honoring and respecting him. However, in this world with its devas, Maras, & Brahmas, in this generation with its brahmans and contemplatives, its royalty and common-folk, I do not see another brahman or contemplative more consummate in release than I, on whom I could dwell in dependence, honoring and respecting him.
"It would be for the sake of perfecting an unperfected aggregate of knowledge and vision of release that I would dwell in dependence on another brahman or contemplative, honoring and respecting him. However, in this world with its devas, Maras, & Brahmas, in this generation with its brahmans and contemplatives, its royalty and common-folk, I do not see another brahman or contemplative more consummate in knowledge and vision of release than I, on whom I could dwell in dependence, honoring and respecting him.
"What if I were to dwell in dependence on this very Dhamma to which I have fully awakened, honoring and respecting it?"
Then, having known with his own awareness the line of thinking in the Blessed One's awareness — just as a strong man might extend his flexed arm or flex his extended arm — Brahma Sahampati disappeared from the Brahma-world and reappeared in front of the Blessed One. Arranging his upper robe over one shoulder, he saluted the Blessed One with his hands before his heart and said to him: "So it is, Blessed One! So it is, One-Well-Gone! Those who were Arahants, Rightly Self-awakened Ones in the past — they, too, dwelled in dependence on the very Dhamma itself, honoring and respecting it. Those who will be Arahants, Rightly Self-awakened Ones in the future — they, too, will dwell in dependence on the very Dhamma itself, honoring and respecting it. And let the Blessed One, who is at present the Arahant, the Rightly Self-awakened One, dwell in dependence on the very Dhamma itself, honoring and respecting it."
That is what Brahma Sahampati said. Having said that, he further said this:
Past Buddhas,
future Buddhas,
& he who is the Buddha now,
removing the sorrow of many —all have dwelt,
will dwell, he dwells,
revering the true Dhamma.
This, for Buddhas, is a natural law.Therefore one who desires his own good,
aspiring for greatness,
should respect the true Dhamma,
recollecting the Buddhas' Teaching.
This is not a complete answer, but there is this Sutta where the Buddha instructs that people should associate with those superior to them (AN 3.26):
“Bhikkhus, there are these three kinds of persons found existing in the world. What three? (1) There is a person who is not to be associated with, followed, and served; (2) a person who is to be associated with, followed, and served; and (3) a person who is to be associated with, followed, and served with honor and respect.
...
“These, bhikkhus, are the three kinds of persons found existing in the world.”
One who associates with an inferior person declines; one who associates with an equal does not decline; attending on a superior person one develops quickly; therefore you should follow one superior to yourself.
Regarding the relationship between the Buddha and Dhamma there is also this:
"Enough, Vakkali! What is there to see in this vile body? He who sees Dhamma, Vakkali, sees me; he who sees me sees Dhamma. Truly seeing Dhamma, one sees me; seeing me one sees Dhamma."
I think the Buddha was exhorting such out of great compassion for he said this to a dying man who was expressing regret.
