Abraham wanted to understand the Law of Revival of nations. Allah asked him if he believed that it were possible. Abraham said he believed but that he wanted a practical example to educate his heart and mind. Allah told him to take four birds and train them in a kind manner, and then to leave them far apart on each hilltop. And then call them; they will come in haste. (At one call of Abraham, those birds came flying back to him. This is how mankind can be brought to the Word of Allah with decent training, giving them a new life). Know that this Wisdom comes to you from Allah, the Almighty, the Wise.