Facing severe suffering and the mysteries of how God runs the world often leads a person to a conscious choice of deep silence. This quietness is an expression of total acceptance. Rather than complaining, arguing, or crying out against perceived injustice, a person accepts that all pain comes directly from God. Because God does no wrong and suffering is a result of human mistakes, there is no room left for anger or resentment [רד״ק, מצודת דוד, רש״י].
However, this acceptance does not mean all communication is cut off. While a person may stop arguing about a bitter fate, the door remains open to beg and ask God for mercy [ביאור שטיינזלץ]. Beyond a personal surrender to the Creator, this silence also serves as a shield against the surrounding society. A person may choose to stay quiet simply to avoid responding to the insults and mockery of reckless people [אבן עזרא]. The quietness also stems from the deep pain of witnessing a reality where wicked individuals sometimes enjoy honor and peace despite their wrongs, while those who try to do good suffer through sickness and pain. In the face of this painful contrast, the suffering person simply has no words to offer them [מאירי].
Taking a completely different approach, the sudden silence can be understood as an inability to study Torah. When a person suffers, they might worry that their pain is a punishment for neglecting their studies. Instead, the quietness here is a defense. If a person is silent and unable to speak words of Torah, it is only because God has brought about physical pain so severe that study becomes impossible. Therefore, the sufferer cannot be blamed for this lack of learning [אלשיך].
On a deeper philosophical level, this silence represents the end of all questioning about the meaning of human existence. A person stops asking and wondering upon reaching a clear realization: the creation of humanity is entirely unique compared to the rest of the world, directly and exclusively tied to the work of God's own hands [מלבי״ם].