食舊德, 貞厲 終吉, 或從王事, 无成.
Shi 食: to ‘eat it’ – to speak about it but not putting it into practice (謂言已出而反吞之，不實行).
Jiude 舊德: the virtues and good deeds of the former kings and ancestors.
食舊德 therefore means to talk about the virtues of the ancestors but not putting them into practice. Without the proper conduct based on the teachings of the ancient ones the divination (zhen 貞) will be dangerous (li 厲). The outcome will be auspicious (ji 吉), but in royal assignments there will be no accomplishments (see also hexagram 2, line 3), as you do not have the full support of the forefathers .
Talking about old virtues but not practising them.
To divine will be dangerous.
In the end auspicious.
There is participation in royal affairs,
But no accomplishments.
Interesting! Can you say more about ‘eating’ as ‘talking about it but not putting it into practice’? Is that something it means in more-or-less contemporary texts?
No, in contemporary texts it only deals with food. But there is the expression shiyan 食言, to “eat one’s words”, meaning to go back on what you promised. That text says that 食舊德 means that the divination 貞 will be 厲, ‘troublesome/dangerous/difficult’. To me this implies that 食舊德 is not something that is approved of. I have read several texts in which 舊德 is read as ‘(in-)heritage’ but to my knowledge this phrase never carried that meaning.