Poole on 1 Samuel 4:12, 13: Message of Defeat and Disaster!
Verse 12: And there ran a man of Benjamin out of the army, and (2 Sam. 1:2) came to Shiloh the same day with his clothes rent, and (Josh. 7:6; 2 Sam. 13:19; 15:32; Neh. 9:1; Job 2:12) with earth upon his head.
[A man of Benjamin] The Hebrews imagine that this was Saul (Lapide).
[On that day] On the same day, understanding, of the conflict (Vatablus).
[And sprinkled with dust on his head] Hebrew: and earth was upon his head. אֲדָמָה/earth; namely, dust. Thus the word is taken in Joshua 7:6; Job 2:12 (Piscator). For the sake of repentance and sorrow was this done; perhaps, from the custom of those communicating their sorrows; so that those hearing might prepare for the blow, since they first speak by their emeanor, and then by mouth (Mendoza).
With his clothes rent, etc.: The usual rites in great sorrows. See Genesis 37:29; Joshua 7:6, etc.; 2 Samuel 1:2, 11.
Verse 13: And when he came, lo, Eli sat upon (1 Sam. 1:9) a seat by the wayside watching: for his heart trembled for the ark of God. And when the man came into the city, and told it, all the city cried out.
[Eli was sitting upon the magistrate’s chair (thus the Syriac, Tigurinus, Castalio, Vatablus), or the episcopal seat (Jonathan), throne (Montanus, Junius and Tremellius, Piscator)] But the Septuagint adds, by the gate, or entrance. Question: Near what gate was Eli sitting? The gate of the city? of his own house? or of the very Temple? Near the Temple he sat, and fell; for there he had been accustomed to sit, 1 Samuel 1:9, and where the fault was, there was the punishment (Mendoza). On the throne (Junius and Tremellius). The article is indeed present in the Hebrew, so that it might be able to appear to signify that throne in 1 Samuel 1:9. But, since it is not evident that from that throne the wayside was able to be observed (which is related here as a fact), it is better to think that the article is here put indefinitely; which is to say, on a certain throne; that is, which he had taken care to be placed for him near the way; so that from there he might watch, namely, for some herald coming (Piscator).
Eli sat upon a seat; placed there on purpose for him, that he might soon receive the tidings, which he longed for.
[Looking towards the way, יַ֥ךְ דֶּ֙רֶךְ֙ מְצַפֶּ֔ה] At the hand of the way watching (Montanus) (watching the hand of the way [Drusius]). Before the gate observing the way (Septuagint). In the way waiting (Arabic). Looking toward the way (Tigurinus). And he was facing the way (Munster). Observing the wayside (Junius and Tremellius). At the wayside, watching (Pagnine) (or, and he was waiting [Syriac]). Near the place of the way, near the way leading to the camp, observing, understanding, and awaiting a herald (Vatablus). In the place of watching, Nauclerus and the Master of History have, listening; because Eli was blind, and not able to see (Mendoza). The יַד/hand signifies side, or place, Joshua 8:20; Job 1:14; 37:7; Isaiah 10:5; 56:5. Moreover, in the reading it is יַד/hand; in the writing, יַךְ, he struck: which thus they explain, he smote his heart; or, his heart smote itself, watching the way. The heart strikes itself in great commotions; thus elsewhere, the heart of David smote him. Thus Kimchi (Drusius). But here Kimchi is to no purpose: for here it is not said, יַךְ לֵב, his heart smote, but rather יַ֥ךְ דֶּ֙רֶךְ֙, the way smote: And so it must be said that יַךְ, he smote, is put in the place of יַד/hand on account of the similarity of form (Cappel’s Sacred Criticism 105, 106).
[And his heart was frightened for the Ark of God] Why not also for the people and his sons? Responses: 1. Because he was uncertain about the loss of the Ark; but certain about the death of his sons from the prediction in 1 Samuel 2:34. 2. Because the Ark was dearer to him than his sons were (Mendoza).
His heart trembled for the ark of God; whereby he discovered a public and generous spirit, and a fervent zeal for God, and for his honour and service, which he preferred before all his natural affections and worldly interests, not regarding his own children in comparison of the ark, though otherwise he was a most indulgent father, and had reason to believe that they went out like sheep for the slaughter, according to Samuel’s prediction.
 Hebrew: וַיָּ֤רָץ אִישׁ־בִּנְיָמִן֙ מֵהַמַּ֣עֲרָכָ֔ה וַיָּבֹ֥א שִׁלֹ֖ה בַּיּ֣וֹם הַה֑וּא וּמַדָּ֣יו קְרֻעִ֔ים וַאֲדָמָ֖ה עַל־רֹאשֽׁוֹ׃  Hebrew: וַאֲדָמָ֖ה עַל־רֹאשֽׁוֹ׃.  Joshua 7:6: “And Joshua rent his clothes, and fell to the earth upon his face before the ark of the Lord until the eventide, he and the elders of Israel, and put dust (עָפָר) upon their heads.”  Job 2:12: “And when they lifted up their eyes afar off, and knew him not, they lifted up their voice, and wept; and they rent every one his mantle, and sprinkled dust (עָפָר) upon their heads toward heaven.”  Hebrew: וַיָּב֗וֹא וְהִנֵּ֣ה עֵ֠לִי יֹשֵׁ֙ב עַֽל־הַכִּסֵּ֜א יַ֥ךְ דֶּ֙רֶךְ֙ מְצַפֶּ֔ה כִּֽי־הָיָ֤ה לִבּוֹ֙ חָרֵ֔ד עַ֖ל אֲר֣וֹן הָאֱלֹהִ֑ים וְהָאִ֗ישׁ בָּ֚א לְהַגִּ֣יד בָּעִ֔יר וַתִּזְעַ֖ק כָּל־הָעִֽיר׃  Hebrew: עֵ֠לִי יֹשֵׁ֙ב עַֽל־הַכִּסֵּ֜א.  Johannes Nauclerus (1425-1516) was the rector, and later the chancellor, of the university at Tübingen, Germany. He is most remembered for his World Chronicle.  The Qere.  Joshua 8:20: “And when the men of Ai looked behind them, they saw, and, behold, the smoke of the city ascended up to heaven, and there was not in them places (וְלֹא־הָיָ֙ה בָהֶ֥ם יָדַ֛יִם) to flee this way or that way: and the people that fled to the wilderness turned back upon the pursuers.”  Job 1:14: “And there came a messenger unto Job, and said, The oxen were plowing, and the asses feeding beside them (עַל־יְדֵיהֶם, at their hands)…”  Job 37:7: “He sealeth up the hand of every man (בְּיַד־כָּל־אָדָ֥ם יַחְתּ֑וֹם, on every side He hath sealed); that all men may know his work.”  Isaiah 10:5: “O Assyrian, the rod of mine anger, and the staff in their hand (בְיָדָם, in their place) is mine indignation.”  Isaiah 56:5: “Even unto them will I give in mine house and within my walls a place (יָד) and a name better than of sons and of daughters: I will give them an everlasting name, that shall not be cut off.”  1 Samuel 24:5; 2 Samuel 24:10.