“And Ionathan caused Dauid to sweare againe, because he loued him: for he loued him as he loued his owne soule.”
1611 King James Version (KJV)
20:17 Swear again - Heb. and Jonathan added or proceeded to make David swear; that is, having himself sworn to David or adjured David, in the foregoing verse, he here requires David's oath to him, by way of restipulation or confirmation. Loved him - Because he had a true friendship for David, he desired that the covenant might be inviolably observed through all their generations.