A divine oath establishes a harsh reality regarding the limits of personal merit in the face of severe judgment. God vows that the presence of profoundly righteous individuals cannot shield a sinful generation from consequence. Even if the three extraordinarily righteous men mentioned previously were living in the land, strict justice dictates that their good deeds would not benefit anyone but themselves [מצודת דוד, ביאור שטיינזלץ].
The decree is so absolute that it extends even to young children, whether they are the offspring of these righteous men or the children of others. Though these young sons and daughters are innocent and have not yet committed their own sins, they will not be spared; instead, they will suffer the consequences of their parents' guilt [רד״ק, מלבי״ם]. The severity of this judgment is further emphasized by the failure of natural defenses. Under normal circumstances, a large group of people stands a better chance of surviving an attack by wild beasts. Yet, in this case, even a sizable group of children will find no safety [מלבי״ם].
Ultimately, the righteous men will survive, but they will only be able to save themselves. Their inability to protect those around them stems from a slight trace of guilt that clings to them, a consequence that comes simply from living among a wicked society [רד״ק].