What is the legitimate position regarding a friend who procrastinated in paying the value of a receipt for the sale of agricultural land, after he admitted to receiving the amount?

Since your friend has admitted to lying and that he received the rest of the payment, he must pay it according to what was agreed upon in the contract between you and him. If he refuses, you can complain to the relevant authorities to compel him to pay what is due, or mediate through someone who holds influence and status with him for this purpose, without resorting to the courts, especially if you do not possess evidence to prove your right against him, and he might deny before the judiciary what he had admitted.