Verse 16: Now therefore (Ex. 14:13, 31) stand and see this great thing, which the LORD will do before your eyes.
Stand: By standing he intends not the posture of their bodies, but the consistency of their minds, by serious and fixed consideration.
Verse 17: Is it not (Prov. 26:1) wheat harvest to day? (Josh. 10:12; 1 Sam. 7:9, 10; Jam. 5:16-18) I will call unto the LORD, and he shall send thunder and rain; that ye may perceive and see that (1 Sam. 8:7) your wickedness is great, which ye have done in the sight of the LORD, in asking you a king.
[Is it not the harvest of wheat? (thus Jonathan, Munster, Tigurinus, similarly the Syriac, Piscator, Tigurinus), הֲל֤וֹא קְצִיר־חִטִּים֙] Is it not the harvest of grain? (Septuagint, Montanus). Is this not the day or time of the harvest? (Junius and Tremellius, Arabic, Pagnine). Question: Whether this was a miracle? Response: In this way. For, at that time rains are not wont to be in Palestine (Munster, Vatablus, Drusius); as Jerome, an eyewitness, writes on Amos 4:7 (Lapide). That thundering was beyond nature at the time of the harvest, and so it was marvelous; because thunderings happened only in the spring and autumn. The reason for which that they are agitated by the collision of heat and cold; which collision is not able to happen in the winter, with cold predominating, nor in summer, with heat predominating: especially in hot lands, of which sort is Syria: for among us thunderings are not rare in summer (Castalio). He says the harvest of wheat, not of barley: because in the latter, since it is prior, it rains sometimes (Mendoza out of Tostatus). Therefore, from that untimely and inexpedient rain, he indicated that the petition of the people, namely, that he would give them a king, was inexpedient (Mariana). But, however the matter stands, it was fair weather when these things were said (Vatablus). The harvest of wheat is today, a clear day, for which sort reapers hope (Grotius). A harvest day, that is, a clear sky, which sort is seasonable at the time of harvest (Junius, Malvenda). As if he should say, such were not accustomed to happen at that time: and if they do sometimes happen, yet not so suddenly, or unexpectedly; just as it happened upon the prayers of Samuel, without preceding disposition of the air (Lyra, similarly Mendoza). Moreover, that this storm was unexpectedly heavier, is indicated by the fact that it threatened present death to the people, verse 19, that we die not; and that it compelled them to confess unwillingly that they had sinned most grievously (Tirinus on Vatablus on verse 18).
At wheat harvest it was a rare thing in those parts to have thunder or rain, as the Scripture oft implies; and St. Jerome affirms, who was an eyewitness of it; the weather being more constant and certain in its seasons there, and in divers other parts, than it is with us who live in islands, as all travellers inform us.
[And ye shall know and see, וּדְע֣וּ וּרְא֗וּ] An elegant paronomasia (Piscator). Both know and see (Pagnine), that is, then ye shall know and understand (Vatablus). For, I pray that this sign be given by God, so that it might be a divine testimony of the truth that I now express; namely, that ye have done wickedly in asking for a King (Menochius). Samuel, either taught by divine instinct, or led by a good and simple heart, asked for this miracle: 1. For the advantage of the people; so that they might be induced to acknowledge their sin, if not with human words, then by divine wonders. 2. For his authority. God excited those thunderings (says Rabbi Salomon in Lyra), so that he might check the obstinacy of the people: for, if such was the strength of Samuel, that he was able to shake the heavens, and to call down thunderings; how was he not able to rout an enemy, and to lead the Republic? (Mendoza).
He shall send thunder and rain; that by this unseasonable and pernicious storm you may understand that God is displeased with you; and also how foolishly and wickedly you have done in rejecting the government of that God, at whose command are all things, both in heaven and in earth.
[Asking a king] Understanding, some other than Him, namely, Jehovah (Vatablus).
Verse 18: So Samuel called unto the LORD; and the LORD sent thunder and rain that day: and (Ex. 14:31; see Ezra 10:9) all the people greatly feared the LORD and Samuel.
[And all the people feared] The Lord, whom the thunderings, rains, and storms were serving: and Samuel, who was so easily obtaining those (Menochius).
All the people greatly feared…Samuel: Who had such great power and favour with God.
Verse 19: And all the people said unto Samuel, (Ex. 9:28; 10:17; Jam. 5:15; 1 Johb 5:16) Pray for thy servants unto the LORD thy God, that we die not: for we have added unto all our sins this evil, to ask us a king.
[Pray] The storm, which compelled the people, formerly obstinate, to cry out, etc., was not light (Sanchez). They, being conscious of their sins, did not have the confidence to entreat; but they were seeing the Samuel’s prayer, altogether efficacious to obtain (Mendoza).
[For thy servants] Just a little before this, they wrested themselves from the servitude of Samuel; now they subject themselves to him against: so that they, perishing outside of that, now returning to that, might be saved. But I am afraid that they profess themselves Samuel’s servants by an officious lie, rather than by true obedience (Mendoza).
Pray for thy servants; for so we shall still own ourselves to be, though we have got another master.
[Unto the Lord thy God] That is to say, who is wont to hear thee (Vatablus). They do not say our God, because they knew that they had offended Him (Menochius). Sinners dare not call God their own (Mendoza).
Unto the Lord thy God, whom thou hast so great an interest in, and canst so easily prevail with for any mercy, whilst we are ashamed and afraid to call him our God, because we have so highly offended him. That we die not; that this terrible storm may be taken away, lest our persons and the fruits of the earth be all destroyed. To ask us a king: so horribly were they biassed with their prejudices and passions, that nothing but a miracle could convince them of this particular sin.
 Hebrew: גַּם־עַתָּה֙ הִתְיַצְּב֣וּ וּרְא֔וּ אֶת־הַדָּבָ֥ר הַגָּד֖וֹל הַזֶּ֑ה אֲשֶׁ֣ר יְהוָ֔ה עֹשֶׂ֖ה לְעֵינֵיכֶֽם׃  Hebrew: הֲל֤וֹא קְצִיר־חִטִּים֙ הַיּ֔וֹם אֶקְרָא֙ אֶל־יְהוָ֔ה וְיִתֵּ֥ן קֹל֖וֹת וּמָטָ֑ר וּדְע֣וּ וּרְא֗וּ כִּֽי־רָעַתְכֶ֤ם רַבָּה֙ אֲשֶׁ֤ר עֲשִׂיתֶם֙ בְּעֵינֵ֣י יְהוָ֔ה לִשְׁא֥וֹל לָכֶ֖ם מֶֽלֶךְ׃  Hebrew: וְיִתֵּ֥ן קֹל֖וֹת.  That is, departing from conventional usage.  That is, a play on words.  Hebrew: וַיִּקְרָ֤א שְׁמוּאֵל֙ אֶל־יְהוָ֔ה וַיִּתֵּ֧ן יְהוָ֛ה קֹלֹ֥ת וּמָטָ֖ר בַּיּ֣וֹם הַה֑וּא וַיִּירָ֙א כָל־הָעָ֥ם מְאֹ֛ד אֶת־יְהוָ֖ה וְאֶת־שְׁמוּאֵֽל׃  Hebrew: וַיֹּאמְר֙וּ כָל־הָעָ֜ם אֶל־שְׁמוּאֵ֗ל הִתְפַּלֵּ֧ל בְּעַד־עֲבָדֶ֛יךָ אֶל־יְהוָ֥ה אֱלֹהֶ֖יךָ וְאַל־נָמ֑וּת כִּֽי־יָסַ֤פְנוּ עַל־כָּל־חַטֹּאתֵ֙ינוּ֙ רָעָ֔ה לִשְׁאֹ֥ל לָ֖נוּ מֶֽלֶךְ׃