The commandments of the Decalogue are called the ten words or ten commandments, because “ten” signifies all; consequently the ten words mean all things of the Word, and thus all things of the church in brief.
All things of the Word and all things of the church in brief are meant, because there are in each commandment three interior senses, each sense for its own heaven, for there are three heavens. The first sense is the spiritual moral sense; this is for the first or outmost heaven; the second sense is the celestial spiritual sense, which is for the second or middle heaven; and the third sense is the Divine celestial, which is for the third or inmost heaven. There are thus three internal senses in every least particular of the Word. For from the Lord, who is in things highest, the Word has been sent down in succession through the three heavens even to the earth, and thus has been accommodated to each heaven; and therefore the Word is in each heaven and I may say in each angel in its own sense, and is read by them daily; and there are preachings from it, as on the earth.
For the Word is Divine truth itself, thus Divine wisdom, going forth from the Lord as a sun, and appearing in the heavens as light. Divine truth is the Divine that is called the Holy Spirit, for it not only goes forth from the Lord but it also enlightens man and teaches him, as is said of the Holy Spirit. As the Word in its descent from the Lord has been adapted to the three heavens, and the three heavens are joined together as inmosts are with outmosts through intermediates, so, too, are the three senses of the Word; which shows that the Word is given that by it there may be a conjunction of the heavens with each other, and a conjunction of the heavens with the human race, for whom the sense of the letter is given, which is merely natural and thus the basis of the other three senses. That the ten commandments of the Decalogue are all things of the Word in brief can be seen only from the three senses of those commandments, which are as above stated.
What these three senses in the commandments of the Decalogue are can be seen from the following summary explanation. The first commandment, “Thou shalt not worship other gods beside Me,” involves in the spiritual moral sense that nothing else nor anyone else is to be worshipped as Divine; nothing else, that is, Nature, by attributing to it something Divine of itself; nor anyone else, that is, any vicar of the Lord or any saint. In the celestial spiritual sense it involves that one God only is to be acknowledged, and not several according to their qualities, as the ancients did, and as some heathens do at this day, or according to their works, as Christians do at this day, who make out one God because of creation, another because of redemption, and another because of enlightenment.
This commandment in the Divine celestial sense involves that the Lord alone is to be acknowledged and whorshipped, and a trinity in Him, namely, the Divine itself from eternity, which is meant by the Father, the Divine Human born in time, which is meant by the Son of God, and the Divine that goes forth from both, which is meant by the Holy Spirit. These are the three senses of the first commandment in their order. From this commandment viewed in its threefold sense it is clear that it contains and includes in brief all things that concern the essence of the Divine.
The second commandment, “Thou shalt not profane the name of God,” contains and includes in its three senses all things that concern the quality of the Divine, since “the name of God” signifies His quality, which in its first sense is the Word, doctrine from the Word, and worship of the lips and of the life from doctrine; in its second sense it means the Lord’s kingdom on the earth and the Lord’s kingdom in the heavens; and in its third sense it means the Lord’s Divine Human, for this is the quality of the Divine itself.
In the other commandments there are likewise three internal senses for the three heavens; but these, the Lord willing, will be considered elsewhere.
As the Divine truth united to Divine good goes forth from the Lord as a sun, and by this heaven and the world were made (John 1:1, 3, 10), it follows that it is from this that all things in heaven and in the world have reference to good and to truth and to their conjunction in bringing forth something. These ten commandments contain all things of Divine good and all things of Divine truth, and there is also in them a conjunction of these. But this conjunction is hidden; for it is like the conjunction of love to the Lord and love toward the neighbor, Divine good belonging to love to the Lord, and Divine truth to love toward the neighbor; for when a man lives according to Divine truth, that is, loves his neighbor, the Lord flows in with Divine good and conjoins Himself. For this reason there were two tables on which these ten commandments were written, and they were called a covenant, which signifies conjunction; and afterward they were placed in the ark, not one beside the other, but one above the other, for a testimony of the conjunction between the Lord and man. Upon one table the commandments of love to the Lord were written, and upon the other table the commandments of love toward the neighbor. The commandments of love to the Lord are the first three, and the commandments of love toward the neighbor are the last six; and the fourth commandment, which is “Honor thy father and thy mother,” is the mediating commandment, for in it “father” means the Father in the heavens, and “mother” means the church, which is the neighbor.
from Spiritual Life and the Word of God