All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Payment dates stipulated in commutative contracts, such as sale and Ijarah, must be abided by. Thus, it is unlawful to claim a debt ahead of its due time since Allah the Almighty Says {What means}: " O ye who believe! fulfil (all) obligations. Lawful unto you (for food) are all four-footed animals, with the exceptions named: But animals of the chase are forbidden while ye are in the sacred precincts or in pilgrim garb: for Allah doth command according to His will and plan." {Al-Mai`da,1}. Al-Shafie (May Allah be pleased with him) said: "When a creditor passes away, debtors must pay on due dates since the death of the former doesn`t make debts due ahead of their schedule. On the other hand, even when a debtor dies, I haven`t heard any of the scholars saying that debts become due ahead of schedule." {Al-Umm, V.3:P.216}.
When the merchant cashes a cheque ahead of schedule, his misconduct takes two aspects:
First: He has cashed deferred payment before its due time.
Second: He has hindered other creditors from taking their already due debts.
In conclusion, the fine imposed by the bank on withdrawal of cheque ahead of schedule must be paid by the person who had done so. However, it is unlawful for the issuer of cheque to take the twenty JDs as a compensation for the harm inflicted upon him by the creditor and his misconduct. This is because such harm has no value in Sharia. And Allah the Almighty Knows Best.