In Genesis 14:14, this signifies the holy things of combat in temptations, for 18 is composed of three and six. (Arcana Coelestia 1709)

1709. 'Three hundred and eighteen men' means the nature of those goods, that is to say, they are the holy things employed in conflict. The number eighteen entails this, as also does the number three hundred, for these numbers are compounded from three and six. Three means that which is holy, as shown in 720, 901, and six means conflict, as shown in 737, 900. Abram's bringing out of such a number of men is true historically; but still it was also representative, as is every historical detail of the Word recorded in the five Books of Moses, and in the Books of Joshua, Judges, Samuel, Kings, Daniel, and Jonah, where in like manner numbers embody arcana within them. For nothing has been written in the Word that was not of such a representative nature. If it were not representative it would not be the Word and it would never have been recorded that Abram brought out three hundred and eighteen, and also that they were trained and were born in his house, besides many other details mentioned in this chapter.