There is much difference of opinion among the commentators...
There is much difference of opinion among the commentators as to the exact meaning. Some, of course, say that they mean the same two fruits that contain the extraordinary nutritive and creative properties. Some others believe that they refer to the two mountains on which the two cities of Damascus and Jerusalem are located, since these two sacred cities are the lands where many great prophets of Allah have appeared.
These two oaths coordinate with the third and fourth oaths that refer to the other sacred lands. Some have also said that these two mountains are called /tin/ ‘fig' and /zaytun/ ‘olive', because the fig trees are cultivated on one and olives on the other.
Again, some believe that /tin/ ‘fig' refers to the time of Adam when he and Eve clothed themselves with the leaves of the fig tree, in Heaven; and /zaytun/ 'olive' refers to the last stage of the deluge at the time of Noah when he sent a pigeon out to search for a piece of land appearing after the flood and it came back bringing a small branch from an olive tree by which Noah understood that the flood was over and dry land had appeared, (hence, the olive branch is a symbol of peace and security).
Furthermore, some think that the term /tin/ ‘fig' refers to Noah's Mosque which was built on Mount Judi of the Ararat range; and that /zaytun/ ‘olive' refers to Jerusalem. The appearance of the verse, at first glance, denotes to the two known fruits, but with paying close attention to the following oaths they are apt to be two mountains or two sacred centers that are respected.
There is a tradition from the Holy Prophet (S) which says that Allah selected four cities, among all cities, and He stated these first three verses about them: "By the Fig and the Olive," "And (Mount) Tur of Sinin," "And the city of security (Mecca)," that /tin/ is Medina, /zaytun/ is Jerusalem, /tur-i-sinin/ is Kufa, and /hath-al-balad-il-amin/ (the city of security) is Mecca.[^2] The purpose of using the term /tur-i-sinin/ as rendered by some commentators, seems to be /tur-i-sina/ (the Mount of Sina) where olive trees, full of fruit, are found.
Sina is interpreted as a Mount full of bounties, or full of trees, or beautiful; it is the same Mount that Moses used to visit to perform his supplications. Some, also, believe that it is a mountain near Kufa and in the land of Najaf. Some have cited that /sinin/ and /sina/ are one in the same which mean 'bountiful'.