“Fear not,” he told them again very decidedly that they had done wrong, but that now they were not to turn away from the Lord, but to serve Him with all their heart, and not go after vain idols. To strengthen this admonition, he repeats the תּסוּרוּ לא in 1Sa 12:21, with the explanation, that in turning from the Lord they would fall away to idols, which could not bring them either help or deliverance. To the כּי after תּסוּרוּ the same verb must be supplied from the context: “Do not turn aside (from the Lord), for (ye turn aside) after that which is vain.” התּהוּ, the vain, worthless thing, signifies the false gods. This will explain the construction with a plural: “which do not profit and do not save, because they are emptiness” (tohu), i.e., worthless beings (elilim, Lev 19:4; cf. Isa 44:9 and Jer 16:19).
Verse 22
“For (כּי gives the reason for the main thought of the previous verse, 'Fear not, but serve the Lord,' etc.) the Lord will not forsake His people for His great name's sake; for it hath pleased the Lord (for הואיל, see at Deu 1:5) to make you His people.” The emphasis lies upon His. This the Israelites could only be, when they proved themselves to be the people of God, by serving Jehovah with all their heart. “For His great name's sake,” i.e., for the great name which He had acquired in the sight of all the nations, by the marvellous guidance of Israel thus far, to preserve it against misapprehension and blasphemy (see at Jos 7:9).
Verse 23
Samuel then promised the people his constant intercession: “Far be it from me to sin against the Lord, that I should cease to pray for you, and to instruct you in the good and right way,” i.e., to work as prophet for your good. “In this he sets a glorious example to all rulers, showing them that they should not be led astray by the ingratitude of their subordinates or subjects, and give up on that account all interest in their welfare, but should rather persevere all the more in their anxiety for them” (Berleb. Bible).
Verses 24-25
Lastly, he repeats once more his admonition, that they would continue stedfast in the fear of God, threatening at the same time the destruction of both king and people if they should do wrong (on 1Sa 12:24, see 1Sa 7:3 and Jos 24:14, where the form יראוּ is also found). “For see what great things He has done for you” (shown to you), not by causing it to thunder and rain at Samuel's prayer, but by giving them a king. עם הגדּיל, as in Gen 19:19.
