Some try to interpret this statement — to the extreme… like we should be Vulcans (to mix genre ). Far from it!
I believe it means we can have emotions but should not let the emotion(s) be the driving force (reason) for why we are acting / reacting. More like… emotion with thought rather than raw emotional responses.
To steal from the Jediism way website:
There is no emotion; there is peace.
I. To an experienced Jedi, this is a pretty self-explanatory line, but for those who might not know its meaning, this line of the Jedi code talks of keeping a state of Jedi Calm.
Jedi Calm is different from normal calm in many different ways. A person is calm only when the situation needs it. They have to try to be somewhat calm in the face of tragedy of excitement, which usually only lasts for a moment, of fails completely. The Jedi, on the other hand, rely on their calm to access the knowledge the Force has to offer them. They must strive to keep this calm at all times so that they might act upon the will of the Force. This calm is taught early on, and strengthened during combat training of the young Jedi. The peace brought on by true calm is the only way to fully access the power of the Force.
II. This does not mean that we are emotionless, just that we do not let our emotions guide our actions. The Jedi’s actions come from compassion for our fellow man.
By keeping our emotions in check, recognizing them, but not let them guide us, we find peace. This statement is a reminder that our actions do not come from our emotions, but from the compassion that comes from our peaceful state of mind.
Not let them (emotions) guide us…
More like — not let emotions so overwhelm us that we stop thinking and let the emotion be the driving ‘force’ —- be it rage, hatred, or love / lust. You can have all those BUT… do not let them be the master to your mind or body. Instead, use that ‘Jedi Calm’ to acknowledge the feelings — and then let them ‘take a step back’ and have your mind/body/spirit focused on the task at hand.