Placing a helpless infant in a river basket is a moment suspended between deep despair and hidden hope. Leaving a watcher nearby represents the human drive to act within a harsh reality, anticipating divine guidance and rescue. The watcher is widely understood to be Miriam [ביאור יש"ר, שטיינזלץ], though some suggest it simply refers to a female family member [אבן עזרא הקצר]. This vigil was not accidental; the mother deliberately stationed her there. She had no intention of leaving her son to starve. Instead, she hoped for his survival and wanted someone to monitor the situation rather than relying on a miracle alone [שד"ל, בכור שור, קאסוטו].
Taking a stand at the riverbank was a complex act. It was a blend of a conscious, energetic decision on the watcher's part, combined with a profound sense that she was being guided and positioned by a higher power [רש"ר הירש, העמק דבר]. She maintained her distance to avoid drawing the suspicion of anyone passing by [ביאור יש"ר]. Her observation was far from passive curiosity; she was actively gathering information to use in a future rescue attempt [רש"ר הירש].
What she expected to happen next is viewed from different perspectives. She might have hoped that an Egyptian would find and adopt the child, which was a common practice at the time [ספורנו]. However, the primary approach among commentators connects her vigil to absolute prophetic confidence. According to ancient tradition, Miriam had foretold that her mother would give birth to the savior of Israel. When the baby was cast into the water and her parents' faith wavered, she held firm. She did not stand at the river to see if the child would be saved, but to witness exactly how the miracle would unfold and her prophecy would come true [רבנו בחיי, תורה תמימה, אלשיך, העמק דבר, ביאור יש"ר, שטיינזלץ].
On a deeper level, the sister symbolizes the Divine Presence. Just as she stood by the water, God always stands beside the righteous during times of trouble, watching over them to bring salvation [רבנו בחיי, מלבי"ם, תורה תמימה]. Furthermore, this act of devotion created a lasting historical impact. Because she waited for Moses and guarded him in his darkest hour, the entire nation of Israel would later wait seven days for her in the desert [תורה תמימה].