Verse 12: Now therefore, I pray you, (see 1 Sam. 20:14, 15, 17) swear unto me by the LORD, since I have shewed you kindness, that ye will also shew kindness unto (see 1 Tim. 5:8) my father’s house, and (Josh. 2:18) give me a true token…
[By the Lord] By whom alone swearing is to be done. Hence her faith shines forth, who comes to terms with them not otherwise than if they were possessing the town; she regarded, not the present condition of her guests with the eyes of the body, but the counsel of God from the viewpoint of faith; since she was acquiescing in this with her whole heart, she was asking that this be sworn (Masius).
By the Lord; by your God, who is the only true God: so she shows her conversion to God, and owns his worship, one eminent act whereof is swearing by his name.
[I have done mercy] Relate this, not so much to the evaded inquisitors of the King, as to the reason of evasion now declared (Masius).
[With my father’s house] Of herself she says nothing, because duty was requiring this of obligation, that they preserve their preserver (Kimchi in Masius). Of a husband and offspring she says nothing, because she had none, as previously mentioned. Concerning her relatives she was especially solicitous, because she knew that they were not yet having their hope place in God, who alone could save (Masius).
My father’s house; my near kindred, which she particularly names, verse 13. Husband and children it seems she had none. And for herself, it was needless to speak, it being a plain and undeniable duty to save their preserver.
[And give a true sign, א֥וֹת אֱמֶֽת׃] A sign of truth (Montanus, Jonathan); or, a true sign (Syriac), a symbol of promise not at all deceitful (Munster); a certain sign (Arabic), by which she could truly and certainly secure herself and her own from destruction, and which she might show the Israelites laying all waste (Bonfrerius).
A true token; either an assurance that you will preserve me and mine from the common ruin; or a token which I may produce as a witness of this agreement, and a mean of my security.
Verse 13: And that ye will save alive my father, and my mother, and my brethren, and my sisters, and all that they have, and deliver our lives from death.
[All that they have] The children of her brothers and sisters, as it is evident from Joshua 6:23 (Masius). In such matters that do not harm the public state, those sent by the people place the people under obligation. For which reason also this faith is kept, Joshua 6:25 and Matthew 1:5. There is a similar history in Judges 1:25 (Grotius).
All that they have, that is, their children, as appears from Joshua 6:23.
 Hebrew: וְעַתָּ֗ה הִשָּֽׁבְעוּ־נָ֥א לִי֙ בַּֽיהוָ֔ה כִּי־עָשִׂ֥יתִי עִמָּכֶ֖ם חָ֑סֶד וַעֲשִׂיתֶ֙ם גַּם־אַתֶּ֜ם עִם־בֵּ֤ית אָבִי֙ חֶ֔סֶד וּנְתַתֶּ֥ם לִ֖י א֥וֹת אֱמֶֽת׃
 See Deuteronomy 6:13; 10:20; Matthew 4:10.
 Hebrew: וְהַחֲיִתֶ֞ם אֶת־אָבִ֣י וְאֶת־אִמִּ֗י וְאֶת־אַחַי֙ וְאֶת־אַחוֹתַ֔י וְאֵ֖ת כָּל־אֲשֶׁ֣ר לָהֶ֑ם וְהִצַּלְתֶּ֥ם אֶת־נַפְשֹׁתֵ֖ינוּ מִמָּֽוֶת׃