As was discussed previously, the Arizal explains that two great spiritual lights emerge when the Torah is removed from the ark and when the Torah scroll is shown to the congregation. Some communities raise the Torah scroll and show it to the congregation after is carried to the Teva, while others, mainly Yerushalmim, walk with an open scroll from the Hechal to the Teva. It is assumed that this latter practice is done in order to benefit immediately from the second of these lights, rather than waiting to show the Torah at the Teva. Rabbi Yaakov Hagiz (Shu”t Hilchot Ketanot, vol. 2, § 255) clarifies, however, that this practice actually developed roughly 350 years ago in Jerusalem. In those days, the typical synagogue was small and not every congregant had room to stand inside and behold the Torah scroll when it was raised at the Teva. As such, it was opened while being carried in procession from the Hechal to the Teva, so that all congregants could see the words of that week’s Parasha. Indeed, the Arizal implies (Sha’ar HaKavanot 48c) that the proper practice is to carry the Torah to the Teva and then open it up to show the congregation, and this is when the second spiritual light emerges. This position is supported by Rabbi Yitzhak Barda (Shu”t Yitzhak Yeranen, vol. 4, § 27). The Moroccan custom and that of most communities follows the Arizal’s opinion.
Summary: The Moroccan custom is that the Torah is opened and shown to the congregation only after it has been brought to the Teva.