Rectified Meaning: 'Moving, hence abundant'—this explains why the hexagram is named Abundance based on the two trigrams.
Moving without brightness cannot be glorious and great; only by relying on brightness to move can one achieve abundance; hence it says, 'Bright and moving, hence abundant.'
'The king attains it; he esteems greatness'—the Dao of abundance and greatness is what a king esteems; the reason a king can attain it is that he is able to esteem greatness.
Rectified Meaning: At midday, the sun shines over all under Heaven; the king is free from sorrow, and his virtue spreads brilliantly, matching the fullness of the midday sun; hence it says, 'Do not worry; it is fitting to be like the sun at midday; it is fitting to shine upon all under Heaven.'
Rectified Meaning: Here Confucius establishes an admonition through Abundance. The above spoke of a king using the virtue of abundance and greatness to illuminate all under Heaven, just like the midday sun.
Yet flourishing must be followed by decline; this is the natural and constant principle. The sun is at its height at midday, but once past noon it slants; the moon is full, but once past its fullness it wanes.
The cold and heat of Heaven come and go; the hills and valleys of Earth shift and change. When full, things ebb with time; when empty, things flow with time.
If even Heaven, Earth, the sun, and the moon cannot endure forever, how could humans, ghosts, and spirits preserve their fullness and flourishing for long? This encourages timely cultivation of virtue, and warns to remember destruction while abiding in preservation.
That this text mentions Heaven and Earth first and humans, ghosts, and spirits later is using the lighter to illustrate the heavier, and placing the honored before the humble.
That the sun and moon precede Heaven and Earth is because, following directly upon 'fitting to be like the sun at midday,' it discusses slanting and waning; using the sun and moon in contrast, it then presents Heaven and Earth alongside them—this is the stylistic convention of writing.