4 Bible Verses about Political Alliances, By Oaths

So Jonathan made a covenant with the house of David, saying, “May the Lord require it at the hands of David’s enemies.” Jonathan made David vow again because of his love for him, because he loved him as he loved his own life.

now therefore, swear to me here by God that you will not deal falsely with me or with my offspring or with my posterity, but according to the kindness that I have shown to you, you shall show to me and to the land in which you have sojourned.”

They said, “We see plainly that the Lord has been with you; so we said, ‘Let there now be an oath between us, even between you and us, and let us make a covenant with you, that you will do us no harm, just as we have not touched you and have done to you nothing but good and have sent you away in peace. You are now the blessed of the Lord.’” Then he made them a feast, and they ate and drank.read more.
In the morning they arose early and exchanged oaths; then Isaac sent them away and they departed from him in peace.

Joshua made peace with them and made a covenant with them, to let them live; and the leaders of the congregation swore an oath to them. It came about at the end of three days after they had made a covenant with them, that they heard that they were neighbors and that they were living within their land. Then the sons of Israel set out and came to their cities on the third day. Now their cities were Gibeon and Chephirah and Beeroth and Kiriath-jearim.read more.
The sons of Israel did not strike them because the leaders of the congregation had sworn to them by the Lord the God of Israel. And the whole congregation grumbled against the leaders. But all the leaders said to the whole congregation, “We have sworn to them by the Lord, the God of Israel, and now we cannot touch them. This we will do to them, even let them live, so that wrath will not be upon us for the oath which we swore to them.”