What was a vassal expected to do besides avoid injurious behavior?

Besides not having an injurious behaviour the vassal was also expected to be  good in advising such that advice would do good to others. By Advising good things to others a vassal was in a way helping God.

A good and faithful vassal would always be helpful, Practical, harmless, easy and Safe. There are almost six qualities that a good vassal follows. The connection was said to be of Faith between God and vassals.

None of the above :]