In MN 138, the Buddha said this:
The Blessed One said: "Monks, I will teach you a statement & its analysis. Listen & pay close attention. I will speak."
"As you say, lord," the monks responded.
The Blessed One said this: "A monk should investigate in such a way that, his consciousness neither externally scattered & diffused, nor internally positioned, he would from lack of clinging/sustenance be unagitated. When — his consciousness neither externally scattered & diffused, nor internally positioned — from lack of clinging/sustenance he would be unagitated, there is no seed for the conditions of future birth, aging, death, or stress."
That is what the Blessed One said. Having said it, the One Well-gone got up from his seat and went into his dwelling.
Then, not long after the Blessed One had left, this thought occurred to the monks: "This brief statement the Blessed One has made, after which he went into his dwelling without analyzing the detailed meaning
I thought the Buddha always kept his promises. Why didn’t he analyze the statement when he said he would?