The freedom to stipulate in the contract is linked to the principle of the authority of the will, as it does not depart from this principle because the will is the source of the conditions. Rather, the freedom of stipulation is the principle of the authority of the will in amending the effects of the contract, but this principle is subject to restrictions in the circle of conditions and has a range of this extent defined by Sharia and law within the controls Certain as part of the freedom to contract. Those who open the door to contracting completely without restrictions also open the door to conditions in contracts, and those who restrict the door to contracting do not respect the conditions except what is consistent with its requirements. The conditions attached to the contract are the conditions that restrict the contract in excess of its original and its requirements, whose purpose is to modify, increase or decrease the regular provisions of the contract, and thus differ from the suspensive conditions that attach the existence of the contract to its existence, so that the contract does not exist unless it exists while in excess of the existence of the contract. Accordingly, the Islamic jurisprudence schools differed in determining this range between broad and narrow for the will to do so, so they set Sharia controls for the conditions attached to the contract. As for the legal legislations, they also set controls that limit the will of the parties to the conditions, most of which are in accordance with Islamic law.