Verse 1: Then (1 Sam. 9:16; 16:13; 2 Kings 9:3, 6) Samuel took a vial of oil, and poured it upon his head, (Ps. 2:12) and kissed him, and said, Is it not because (Acts 13:21) the LORD hath anointed thee to be captain over (Deut. 32:9; Ps. 78:71) his inheritance?
[A lentil-shaped vessel of oil (thus the Septuagint, Pagnine, Montanus, Junius and Tremellius), פַּךְ]] A small vessel (Arabic, Munster, Tigurinus); a vial (Munster). Note that, although the anointing of Kings is commanded by no law, as far as I know, it is employed repeatedly as customary even before those times. See Judges 9:8 (Tirinus almost out of Sanchez). Now, it is indicated by this ceremony that kings, no less than Priests, are sacred to God, and ought to be filled with the anointing of heavenly gifts (Tirinus). The oil was teaching them about their office; which was (after the likeness of oil) to refresh, to care for, to heal, the people. It was also signifying the mercy that they were obliged to show to the people (Martyr). The reasons for anointing were: 1. So that it might be signified, both that the dignity of the King was the highest; and that new strength was infused into him by God. 2. So that kings might be advised to exercise gentleness, charity, etc., towards their subjects. 3. So that they might stand as a type of Christ (Lapide). The Hebrew Kings were also anointed after the example of the Priests; not indeed as Priests, but rather as having much that is sacerdotal; a seat and the right of speaking in the sanctuary, inspection in sacred things, the right of choosing or fixing the High Priest and other Priests, and other things of this sort: yet in a different manner; Priests with the oil smeared crosswise on the forehead, Kings on the top of the head after the manner of a crown. Here, God is said to have anointed Saul, and in verse 24 to have chosen him; namely, κατὰ τὸ θέλημα ἑπόμενον, not τὸ προηγούμενον, according to His consequent, not antecedent, will; for thus the ancients distinguish (Grotius). Moreover, this oil was not the oil of anointing, wherewith David alone, with his posterity, was anointed; but oil of balsam, or of opobalsamum (Drusius out of the Hebrews, similarly Vatablus). שֶׁמֶן signifies ointment and balsam. With which balsam clothes were not stained, for it was after the likeness of water; Pliny’s Natural History 12:25 (Mariana).
Samuel took a vial of oil, and poured it upon his head: This was the usual rite in the designation, as of priests and prophets, so also of kings, as 1 Samuel 16:1, 13; 1 Kings 1:39; 2 Kings 9:1, 3, 6; whereby was signified the pouring forth of the gifts of God’s Spirit upon him, to enable him for the administration of his office, which he might expect, and should receive upon the discharge of his duty.
[And he kissed him] Either, 1. So that he might confer the grace of a prophet upon him, as Christ did by breathing upon, etc. (Theodoret and Procopius in Mendoza). So that he might signify that God is going to be near to him, and equip him with His Spirit (Martyr). Or, 2. As a sign of subjection (Junius, Piscator). Thus in Genesis 41:40; 1 Kings 19:18; Psalm 2:12; Hosea 13:2 (Piscator). It was a kiss of trust and obedience; as it appears, from the custom of those times (Martyr). For the sake of respect, as of a future King, he kissed his hand. See Genesis 41:40; Psalm 2:12 (Grotius). Or, 3. It was a ceremony, whereby Saul was made King. Just like when one is made a Doctor (Lapide out of Tostatus). Or, 4. This kiss arose out of goodwill, rather than the observation of law or custom, since kings were inaugurated (Menochius out of Sanchez). It was a sign of friendship. He does not hate or despise his successor, as others are generally wont to do, but rather does homage to him (Martyr).
And kissed him; partly in token of that reverence which he did owe, and that subjection which he and all the people were shortly to perform to him, whereof kissing was a sign, as Genesis 41:40; 1 Kings 19:18; and partly as a testimony of his sincere friendship and affection to him, and how far he was from envying his successor in the supreme dignity.
[Behold, the Lord hath anointed thee] It is a defective speech (Malvenda). [Thus they translate it:] Behold (or now [Arabic]), the Lord hath anointed thee (Syriac). Thou seest that He hath anointed thee (Stigelius). Hath He not anointed thee? (Septuagint, Tigurinus). Hath He anointed, etc.? (Jonathan). Hath He not anointed thee? (Munster). Knowest thou not that I have anointed thee? (Rabbi Isaiah in Drusius). Is it not? is often used to confirm a matter, and to make a man more ready (Kimchi in Drusius). Is it not that He hath anointed thee? (Pagnine, Montanus). A supplement is required: Is it not the case that He hath anointed thee? The Hebrews pronounce with a question what they wish vehemently to affirm; that is to say, I anoint thee in the name of God, who by this anointing constitutes thee as Captain over His inheritance. Concerning an interrogation of this sort, see Ruth 3:1 (Vatablus); which is to say, It is altogether certain, that God hath anointed thee (Malvenda). Am I not going to do? (I would prefer, am I not doing? that is, what I do: namely, that I kiss thee [Piscator]). For Jehovah anointed thee, etc. (Junius and Tremellius), that is, with the symbol of anointing employed, He constituted, synecdochically. Now, it appears that Saul cast an impediment in the way, as if force were being applied to him, unsuspecting and stupefied by the novelty of the matter: and that, therefore, Samuel checked him with these words. What? Should I not do what I have from the Lord in commissions? etc. For the Hebrew disjunctive accent [he appears to understand the major pause, the Rebia (֗), over הֲל֗וֹא, is it not], and the argument of the matter itself, require these words thus to be explained (Junius, Piscator, Malvenda). Moreover, God is here said to have done what Samuel did by His authority; just as God is said to speak in the prophets; whence that common, thus saith the Lord. Not without reason is pride charged upon Balaam, Numbers 24:15, thus saith Balaam, etc. (Mendoza).
Over his inheritance, that is, over his own peculiar people; whereby he admonisheth Saul that this people were not so much his as God’s; and that he was not to rule and manage them according to his own will and pleasure, but according to the will and mind of God.
 Hebrew: וַיִּקַּ֙ח שְׁמוּאֵ֜ל אֶת־פַּ֥ךְ הַשֶּׁ֛מֶן וַיִּצֹ֥ק עַל־רֹאשׁ֖וֹ וַיִּשָּׁקֵ֑הוּ וַיֹּ֕אמֶר הֲל֗וֹא כִּֽי־מְשָׁחֲךָ֧ יְהוָ֛ה עַל־נַחֲלָת֖וֹ לְנָגִֽיד׃ פַּךְ/vessel is related to פִּכְפֵּךְ/trickle. Opobalsamum is the resinous juice of the balsam-tree.  See John 20:22.  Genesis 41:40: “Thou shalt be over my house, and according unto thy word shall all my people be ruled (וְעַל־פִּ֖יךָ יִשַּׁ֣ק כָּל־עַמִּ֑י, and upon thy mouth all my people shall kiss): only in the throne will I be greater than thou.”  Hebrew: הֲל֗וֹא כִּֽי־מְשָׁחֲךָ֧ יְהוָ֛ה.  Ruth 3:1: “Then Naomi her mother in law said unto her, My daughter, shall I not seek rest for thee, that it may be well with thee (הֲלֹ֧א אֲבַקֶּשׁ־לָ֛ךְ מָנ֖וֹחַ אֲשֶׁ֥ר יִֽיטַב־לָֽךְ׃)?”