Seeing a sack in your dream is generally considered a symbol of travel or various activities. It can also represent the human body. If the sack is empty, it is interpreted as a sign of death. When you encounter a sack in your life, it may indicate your ongoing activities or travels, which could also reflect your spiritual or physical condition.
From Imam Muhammad Ibn Seerin's Dictionary of Dreams According to Islamic Inner Traditions â entry "Sack" (page 369).
A sack or any packing container in a dream represents travels, or activities in general. A sack in a dream also represents the body of a human being. An empty sack in a dream then means death. Seeing a sack within a sack in a dream represents the knowledge one benefited from during his life in this world. If the second sack contains money in the dream, it means that one's knowledge is true. If it contains change, it means that one is still studying and needs to further his knowledge. A sack in a dream also represents one's personal and secret life. In a dream, if one makes a cut through a sack and throws its contents asunder, it means that his private and intimate life will be exposed and becomes the subject of people's talk. Ifone's money falls through a hole in the bag or a purse he carries, the bag also represents his body and the money represents his soul, which is an indication of his death. If one finds termites or moths inside his sack in a dream, it also means death. Thus, a sack in a dream denotes what a person represents, or it could mean one's heart. (Also see Bag; Pouch; Purse,' Suitcase; Trunk)
Note: Islamic dream interpretation depends on the dreamer's circumstances and state. This is a general guide drawn directly from the source book.