Did the Buddha break his promise?

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?