太上《道德真经》中所概说的“道”，是道教的核心教理。道教所以称为“道教”，《云笈七签》以“道德”部为第一类，《道教义枢》也以《道德义》作为开宗明义第一义，都是因为道教徒要以“道”为核心教理和最高信仰。所以《道典论》中说，道士者，要以“道”为事。
The "Tao" outlined in the "Tao Te Ching" is the core doctrine of Taoism. The reason why Taoism is called "Taoism" is that the "Yun Ji Qi Qian" takes the "Dao De" section as the first category, and the "Dao Jiao Yi Shu" also takes the "Dao De Yi" as the first principle, all because Taoists want to take "Tao" as the core doctrine and the highest belief. Therefore, "Dao Dian Lun" says that Taoists should take "Tao" as their business.
太上之道，在道教的信仰中，它是无形、无色、无味、无声、无情、无信的，又是先天地而存在的，并无世不在，无处不有，是生化天地万物一切有形的本源。本无法用有形的文字来称说，但为了便于人们来记述，强名而为“道”。道生化天地万物，是通过无形的元始祖气、并由元始祖气分化为阴阳二气来成就万物的。万物则依各自所禀赋的气质而各成形状，自然生长。在人类生命出现后，道又聚气而成神尊，教育人们明白“道”的宗义，珍重生命，树立符合“道”之体性的人生观。“道”在宇宙尚未开辟之时，曾变化为元始天尊。在宇宙开辟有了天地之后，变化为灵宝天尊。在成就宇宙万物的过程中，又化生为太上老君道德天尊。此后，太上则历世化生，布说“道”之宗义而被尊为师，至殷武丁时化生为老子，著说《道德真经》，开仙道之宗源。所以道教在创立之后，尊奉元始天尊、灵宝天尊、太上老君为最高尊神，信仰敬拜。使对“道”信仰形象化、人格化。其核心信仰也就是“道”。
The Tao of the Supreme, in the belief of Taoism, is invisible, colorless, tasteless, soundless, emotionless, and faithless. It exists before heaven and earth, and it is everywhere. It is the tangible origin of all things in the world. It cannot be described with tangible words, but in order to facilitate people to record, it is named "Tao". Tao creates all things in the world through the invisible original ancestor qi, and the original ancestor qi is differentiated into yin and yang qi to achieve all things. All things take their own shapes and grow naturally according to their own temperaments. After the emergence of human life, Tao gathered energy and became a god, educating people to understand the doctrine of "Tao", cherish life, and establish a life view that conforms to the nature of "Tao". Before the universe was created, "Tao" was transformed into Yuanshi Tianzun. After the universe was created and heaven and earth were formed, it was transformed into Lingbao Tianzun. In the process of achieving all things in the universe, it was transformed into Taishang Laojun Daode Tianzun. After that, Taishang was reborn in successive generations, preaching the doctrine of "Tao" and was respected as a teacher. In the time of Wu Ding of Yin, he was reborn as Laozi, who wrote "Tao Te Ching" and opened the source of immortality. Therefore, after the founding of Taoism, Yuanshi Tianzun, Lingbao Tianzun, and Taishang Laojun were respected as the highest gods, and they believed in and worshiped them. This made the belief in "Tao" visualized and personified. Its core belief is "Tao".
而在道教修行中，更是以太上之道的义理为根本。因为无上的“道”不但是造物主，至高神圣，而且有着最值得人们崇敬和体悟的高尚品德，有益人们修行和信奉大道者树立良好的人生观。“道”化生万物，以自然无为为法则，任万物自然生长，而且从不因为是万物生化的主宰者而居功自恃。不索求任何报答，毫无一点私自之欲，始终保持以清静为本，柔弱为用。并像水一样处下以利万物，且具有江海一样的胸怀，虚怀若谷。以用文字难以形容的高尚德行成就和养育万物，使自己永恒常存，不生不灭。所以，道教以“道”为教理宗义，教导人们修行“道”一样的品德，度已度人。道教所敬奉的救苦天尊和祖天师等所有神仙真人，由于他们具有“道”一样德行或通过自己的修行而得道，成为“道”又一人格形象，受到世人的敬奉。
And in Taoist practice, the righteousness of Supreme Tao is the foundation. Because the supreme "Tao" is not only the creator, the supreme and sacred, but also has the most noble character worthy of people's respect and understanding, which is beneficial for people who practice and believe in the Tao to establish a good outlook on life. "Tao" creates all things, takes natural inaction as the law, allows all things to grow naturally, and never takes credit for itself because it is the master of all things. It does not ask for any reward, has no selfish desires, and always maintains tranquility as the basis and weakness as the use. It is like water, lying down to benefit all things, and has a mind like the river and the sea, and is open-minded. It achieves and nurtures all things with noble virtues that are difficult to describe in words, making itself eternal and immortal. Therefore, Taoism takes "Tao" as its doctrine and teaches people to practice the same virtues as "Tao" to save themselves and others. All the gods and immortals worshipped by Taoism, such as the Heavenly Master of Salvation and the Ancestor Heavenly Master, have become another personality image of "Tao" because they have the same virtues as "Tao" or have obtained Tao through their own practice, and are worshipped by the world.