Dilemma in the Definition of 'Abettor'

Mainly from textbooks, I get the feeling that the term 'abettor' in IPC 107 is explained in a rather vague manner. Abettor is defined as a person who incites or instigates another to commit an offence, without being physically present at the scene. But what exactly constitutes 'incitement' or 'instigation'? Is it limited to verbal statements or can it also be implied through actions or gestures? Can an online post or a message be considered an abetment if it leads to the commission of a crime? How do we differentiate between mere encouragement and actual abetment? Any real-world examples or court judgments that clarify this concept would be super helpful for Judicial Services aspirants!