One who takes a pledge from his fellow if he had been certain that his fellow would pay him back earlier than agreed upon and would, out of sheer kindness, reward him for waiting for his money with twice the sum that was owed him then he would never have taken a pledge from him.
And as for the Creator, may He be exalted Whose benevolence and great favor present and past are known to us Who is known to requite acts of charity and obedience with a reward that cannot be imagined, let alone described. It is much more of a disgrace to demand a pledge from Him.