ט֚וֹב אֲשֶׁ֣ר תֶּאֱחֹ֣ז בָּזֶ֔ה וְגַם־מִזֶּ֖ה אַל־תַּנַּ֣ח אֶת־יָדֶ֑ךָ כִּֽי־יְרֵ֥א אֱלֹהִ֖ים יֵצֵ֥א אֶת־כֻּלָּֽם׃
Tu feras bien de t’attacher à l’une des méthodes sans que ta main lâche l’autre: celui qui craint Dieu se tire d’affaire en toutes choses.
Tze'enah Ure'enah
“Good that you should grasp” [7:18]. It is good that you should hold on to justice and you should also hold on to injustice. That is to say, when the righteous one and prophet commands you to do something and you think it is an injustice against God, you should still hold on to it. The one who fears God holds on to justice and injustice, no matter what it is.
Rashi
It is best to take hold of one, etc. Grasp both, righteousness and wickedness. If the righteous prophet told you something that appears to you as being evil, e.g., what Shmuel said to Shaul, let it not be taken lightly by you to doubt it.
Kohelet Rabbah
“It is good that you grasp this, and from that, too, do not withdraw your hand, for one who fears God will fulfill them all” (Ecclesiastes 7:18).
“It is good that you grasp this,” this is Bible, “and from that, too, do not withdraw your hand,” this is Mishna; “for one who fears God will fulfill them all,” like Rabbi Abbahu of Caesarea.
“It is good that you grasp this,” this is Bible, “and from that, too, do not withdraw your hand,” this is Mishna; “for one who fears God will fulfill them all,” like Rabbi Abbahu of Caesarea.
Rashi
Will discharge his duty to both. Both of them, to preserve the righteousness and the wickedness according to their rule.