Dispute over land between my father and maternal cousin brother

We are Hindu by religion. My father had bought a small piece of land. All the documents and registration is done in name of my father and we have the relevant documents with us. My Maternal side cousin brother requested by father to give the land to him for farming business just via a verbal note. My father agreed, as he committed that after few months he would buy the land and provide the money to my father, as he is our family member my father agreed until he betrayed us. Now, the guy is bullying my father by saying that he would not move away from the land. Neither he will leave the land nor buy it. Now he has made few false agreements using fake signatures stating my father had made an agreement and provided the land to him. He is about to file a case to acquire the land as he is rich and he can afford wasting time, money & false evidences, but all the documents are in my fathers name and dispute is going on for more than 4 yrs now. Please help me if my father will win the case?