According to Prof. Ren Jiyu, there is no negation or denial of the existence of the Lord to be found in such Chinese classics as The Book of Poetry (Shi Jing), The Book of Zuo Zhuan (Zuo Zhuan), and Conversations of the States (Guo Yu). In fact, nobody dared then to underestimate the supreme position of the Lord, despite a few complaints about injustice in the aspects of reward and punishment which were believed to be blindly exercised by the Lord. It was rather paradoxical that they would hate and curse the Lord of Heaven in view of the injustice they encountered, and still confess to Him when wronged or ill-treated or harried into natural disasters, etc. In striking contrast, Lao Zi's perception of the Dao instead of the Lord turns out to be overarching, for it works as the ancestor of all things. The uniqueness of his philosophy also lies in his perspective that Heaven and earth in his terminology represent the sky and the ground.

1.3 (Chapter 6)
The spirit of the valley is immortal.[1] It is called the subtle and profound female.[2]
The gate of the subtle and profound female. Is the root of Heaven and Earth.
It is continuous and everlasting, With a utility never exhausted.

Annotations:
[1] The Chinese expression gu shen (the spirit of the valley) is rather ambiguous. Some Lao Zi scholars (e.g. Yan Fu and Chen Guying) assume that gu signifies a state of emptiness or virtuousness, and shen endless and unpredictable changes. Some other scholars (e.g. Ai Qi) think that gu shen refers to a deity in an empty or virtuous state. I personally agree with Mr. Sha Shaohai, who believes that gu shen implies another name for the Dao itself. In the above context, the lines "The spirit of the valley (gu shen) is immortal. It is called the subtle and profound female" suggest the metaphorical characteristics of the eternal Dao. Such an interpretation appears to correspond to Lao Zi's system of thought as a whole.
[2] The term xuan pin (subtle and profound female) indicates in its concrete sense the female sex organ as a metaphor for the Dao, which is subtle, deep and mysteriously productive. It is worth noting that people in ancient times used to revere what they thought was the magic power contained inside the female organ. This kind of reverence or worship is clearly reflected and expressed in primitive rock paintings and carvings. Nowadays people would probably laugh or jeer at a primitive painting or sculpture portraying the female sex organ in an exaggerated fashion. But we should put ourselves in the position of our ancestors in terms of their primitive cognitive dimension, for that kind of exaggerated manifestation in art denotes some form of natural religious feeling and significance.
Commentary:
This chapter again describes the magical productivity of the Dao It is noticeable that Lao Zi uses the term shen (spirits) in a casual manner and in a pantheistic sense. In contrast, the notion of shen (divine beings) carries somewhat of a religious meaning in both Confucianism and Moism. It should be kept in mind that gu shen (valley spirit) has, as it were, nothing to do with any form of spiritual or divine beings in the above context. It factually refers to the most wonderful Dao featuring vacuity or emptiness, subtlety and constancy.
In addition, the metaphor xuan pin (subtle and profound female organ) for the Dao is employed several times in the Dao De Jing. It symbolizes the invisible power or potentiality of the Dao that produces all beings. The metaphor as such is largely derived from the worship of the female organ for its productiveness and mysteriousness by people in antiquity. The expression, "The gate of the subtle and profound female is the root of heaven and earth," is obviously identical in meaning to that describing the Dao as follows: "Being-without-form is the beginning of Heaven and earth," and as "Being-within-form is the mother of all things."

(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)