Why did Charles V give Malta to the Knights of Rhodes in 1530?

In 1530, Holy Roman Emperor Charles V granted the Maltese archipelago to the Hospitallers—a religious and military order also known as the Knights of Rhodes—following their expulsion from Rhodes by the Ottoman Empire in 1523.12

After seven years as a wandering order without a base, the Knights were given Malta to serve as a new stronghold. In exchange for the territory, the order was required to provide the Emperor's viceroy of Sicily with an annual tribute, which included the presentation of a falcon. This arrangement provided the Knights with a sovereign base from which they could continue their maritime defense of Christian interests in the Mediterranean against Ottoman expansion.123