You actually think you are under some form of persecution

According to the DSM-IV-TR, persecutory delusions are the most common form of delusions in paranoid schizophrenia, where the person feels they are being "tormented, followed, tricked, spied on, or ridiculed", or that their food is being poisoned. They are also often seen in schizoaffecvtive disorder and, as recognized by the DSM-IV-TR, constitute the cardinal feature of the persecutory subtype of delusional disorder, by far the most common. Delusions of persecution may also appear in manic or mixed episodes of bipolar disease, polysubstance abuse, and severe depressive episodes with psychotic features, particularly when associated with bipolar illness.