In general, we tend to be very aware of how knowing what's true leads to doing what is good. That starts as children, with parents telling us not to hit each other and to use good manners, small truths that pretty much force us to behave decently. That continues in adulthood: You don't really want to get up and go to work, but you know you have to, so you do.
So we tend to think of truth as something thrust upon us by external forces, something we have to obey. If you think about it, though, that's really not the case. The love we have for our families, and our desire to care for them, leads to the idea that we have to get up and go to work. Our desire to make people happy around us leads to the idea that we should use good manners. They feel like external ideas, but we only follow them because of internal ideas we have, which come from our desires for good things.
Swedenborg takes that idea to its logical conclusion, regarding every expression of love, even the most elemental, as truth. This is a concept that stretches beyond our normal range of thought. It's easy us to see the statement "I love you" as a "truth," but in this deeper concept the look in our eyes, the warmth of our hugs, the tenderness of a touch is "truth" as well. Put simply, truth is love given form, and the more pure the form, the higher the truth.
With that idea, consider the love that the Lord has (or to say it better, the love that the Lord IS). It's the love that led to the creation of the universe and of reality itself, the love that inevitably led to the creation of humankind, the love that flows to each of us constantly, trying constantly to lead us to acceptance and to heaven. What is the truth flowing from that love; what is its expression? It blows the imagination to think about it, a truth that lies in every particle in the universe, that is intimately tied to every thought had every moment by everyone who has ever lived and will ever live, plans for each of us that extend to eternity and account for every choice we could ever make. To think of it another way, try to imagine the look in the Lord's eyes when He gazes on us, the sound of His voice when he speaks to us, an expression that would convey love greater than we can imagine.
Swedenborg calls this "Divine Truth." And when the Bible uses the term "the Word," that's what it means.
With that in mind, consider the beautiful but cryptic statements of John 1:1: "In the beginning was the Word, and the Word was with God, and the Word was God." God's love has always been and will always be, infinite and perfect. That means the expression of God's love – His truth – has also always been and will always be, infinite and perfect. It is His form; it is Him.
Swedenborg tells us that the Lord has shared this truth with us in various ways since the beginning of humanity. The earliest people, those of the Most Ancient Church, got it automatically, flowing into the inner parts of their minds through heaven. Later, in the Ancient Church, people understood it through nature, seeing the Lord's love expressed in mountains, trees, rivers and movements of the the sun, moon and stars. By using natural language as a container for spiritual language, the Lord expressed that truth within the Bible, inside its stories, laws and prophecies. Then, with humanity at its lowest point, He gave the world His truth in human form as Jesus, so that by accepting and loving Him as Jesus we can open ourselves to His love. Finally, Swedenborg says that his written works - which he says came from the Lord - are themselves a container for Divine Truth, both in speaking plainly about heaven and by unlocking the truth as it is contained in the Bible.
Despite those varied containers and modes of expression, however, the Word itself – the Divine Truth; the Lord's love expressed – has never changed and will never change, as perfect and infinite as the love it holds.