Sam Vara wrote:What did he know? What are those results? And perhaps just as importantly, how did he know them?
From the verse section:
Having given much food as offerings
To those most worthy of offerings,
The donors go to heaven
On departing the human state.
Having gone to heaven they rejoice,
And enjoying pleasures there,
The unselfish experience the result
Of generously sharing with others
Without the Supernatural power of clairvoyance of the Buddha, we could only infer the bliss up there in deva world must be quite spectacular. This sutta reminds me of the skillful means the Buddha employ to get prince Nanda to let go of sensual pleasures with the promise of heavenly sensual pleasures:
When they arrived at the Park, the Buddha questioned Nanda regarding whether he might become a Monk. Although Nanda had just wedded the beautiful Janapada Kalyāni, that same day, he took ordination and joined the community of Monks.
However, Nanda enjoyed no spiritual happiness. His thoughts were constantly directed towards to Janapada Kalyāni and his heart pined for her.
Learning of this, the Buddha took Nanda on a journey to Tavatimsa Heaven or Trāyastriṃśa. On the way Nanda saw a she-monkey that had lost her ears, nose and tail in a fire, clinging to a charred stump. When they reached the heaven abode, Nanda saw beautiful celestial nymphs and the Buddha asked Nanda: "Which do you consider more beautiful? Those nymphs or Janapada Kalyāni?"
Nanda replied: "Venerable Sir, Janapada Kalyāni looks like the scalded she-monkey, compared to those nymphs."
The Buddha said: "Cheer up Nanda. I promise that you will join the company of those nymphs if you persist as I bid you and take pleasure in living the Holy Life."
Upon hearing this, Nanda practiced diligently with the object of winning the celestial nymphs. However, when the other monks learned of Nanda's wish they ridiculed him and he eventually saw his motive as base, and renouncing desire, attained Arhatship.
There is a poem in Theragatha collection of verses believed to have been authored by Nanda praising the Buddha for having become an arahant.
Abeysekera writes: "On realizing the exquisite happiness of Nibbana, Nanda approached the Buddha and thanked Him respectfully by saying, "Lord I release you from your promise of celestial bliss." The Buddha then informed Nanda that He had been released from the promise the moment he had reached the supreme bliss of Nibbana, because the bliss of Nibbana was greater and transcended any celestial bliss