The Gemara in Masechet Megila comments that it is customary to invite the "Gadol" the congregant of greatest stature to perform "Gelila" in the synagogue, as the reward for this Misva equals the rewards for all the other Misvot of the Sefer Torah combined.
Numerous different explanations have been offered for the term "Gelila" used here by the Gemara. The Mishna Berura (Rav Yisrael Meir Kagan of Radin, 1839-1933) explains that the Gemara refers to what we call "Hagbeha" lifting the Sefer Torah and showing the parchment to the congregation. Indeed, the Shulhan Aruch writes that the custom in his time was to sell this honor for large amounts of money, and if it was not purchased, to give it to the most prominent member of the congregation.
Others explain that the Gemara refers to rolling the scroll in preparation for the Torah reading. Another interpretation is that the Gemara speaks of the one who rolls the Torah to close it after Hagbeha, as is done in Ashkenazic communities. It has also been suggested that "Gelila" means the final Aliya of the Torah, when the reading of the entire Torah is completed on Simhat Torah. According to this interpretation, the greatest reward is received by the one who receives this Aliya. Others explain that the Gemara refers to the final Aliya every Shabbat.
In any event, the Halachic authorities observe that although in the past it was customary to invite the person of highest stature for Hagbeha, this is not the custom today. Nowadays, even youngsters are given this honor in order to encourage them to become involved, and in order to avoid arguments that might erupt if it was known that this honor was given to the person of highest stature. However, the Mesader in the synagogue must ensure to choose for this role somebody with strong, steady hands so he can lift the Torah without any trouble. Especially when inviting a youngster for this honor, it must be ascertained that the Sefer Torah is not too heavy for the boy. And if somebody is invited to do Hagbeha but is concerned that he might not be able to hold up the Torah, he must inform the Mesader.
Many people have the misconception that lifting the Torah to show it to the congregation is not a very significant role in the synagogue. As we have seen, at least according to some opinions, this is the greatest of all honors in the synagogue, and a precious Misva. One should therefore not belittle this great privilege, and those who are invited to perform this ritual should certainly not feel offended in any way or feel they are being disrespected.
Summary: Hagbeha, lifting the Sefer Torah to show it to the congregation, is a very significant Misva, which, in the olden days, would be purchased for a good deal of money. Although today it is customary to give this job even to youngsters, even so, one should not belittle the importance of this Misva, which should be looked upon as a great privilege and honor.
