He who possesses De in abundance
Can be compared to a newborn infant.
Poisonous insects will not sting him.
Fierce brutes will not injure him.
Birds of prey will not attack him.
His bones are weak and his sinews tender,
But his grasp is firm.
He does not yet know about the intercourse of male and
female,
But his organ is aroused
For his physical essence is at its height.
He may cry all day without becoming hoarse,
For his innate harmony is simply perfect.
The essence and harmony as such are natural and constant.
To know this is called being wise.[1]
The desire to multiply life's enjoyments means ill omen.[2]
The mind to employ qi excessively suffers fatal stiffness.[3]
Things that have grown strong commence to become old.
This is called "being contrary to the Dao."
Whatever is contrary to the Dao will soon perish.

Annotations:
[1] Contextual studies inform us that Lao Zi's concept of ming (which can be translated literally as "light") means "wise" or "wisdom," while zhi means "knowledge" or "learning." This is testified by Lao Zi's notions such as Zhi ren zhe zhi, zi zhi zhe ming ("He who knows others is learned; he who knows himself is wise." See Chapter 33, DDJ), shi wei wei ming ("This is called subtle wisdom." See Chapter 36, Ibid.), etc.
[2] From a Daoist viewpoint, any desire to increase life's enjoyments in a pleasure-seeking manner will surely harm and injure life itself. It is disastrous to add more to life's enjoyments as well as being against the way of spontaneity or naturalness in Lao Zi's thinking.
[3] The Chinese term qi here means the physically vital force or energy which preserves life. The excessive use of qi will inevitably lead to over-exhaustion and disharmony between Yin and Yang as two kinds of essential and complementary qi in the body. The expression "fatal stiffness" implies lack of vitality or physical decline leading to death. This is in line with Lao Zi's conviction that "the hard and stiff are companions of death" (see Ch. 76, DDJ).

Commentary:
In this chapter, as has been observed by Ren Jiyu, "Lao Zi preaches the philosophy of nonaction as an attitude toward life, and teaches people to return to a state of primitive ignorance. He advocates being like an innocent child without desires. This accords with the criteria of the Dao, and one can avoid disasters by remaining weak, soft and ignorant, otherwise he will soon perish owing to his opposition to the principle of the Dao" (see A Taoist Classic: The Book of Lao Zi, p. 75).
Moreover, we assume that Lao Zi figuratively describes his philosophy of self-preservation in a twofold sense: social and physical. As for the former, it is reflected in the quotation cited above. If viewed from a social dimension, a newborn baby, weak and tender as it is, is free from attack by "poisonous insects," "fierce brutes" and "birds of prey," which are symbolic of evil natured and cold-blooded savages in society, always ready to cut down those who become prominent. If a person were as ignorant and innocent as an infant without desires, he would exist without threatening the interests of anyone else. Therefore he could avoid jealousy, hatred, and danger; or in other words, he could defend, passively or otherwise, and preserve himself. This well responds to the saying that "ignorance is bliss."
With regard to self-preservation in a physical sense, the fact that a newborn infant is taken as a model by Lao Zi is largely due to the fact that it is filled with vitality and has not lost a single grain of its essential qi, or life-force. An innocent child usually lives a natural life, different from adults, who have strong desire and high life-consciousness. Lao Zi believes that "the tender and soft are companions of life," and so is the child. Hence, he who wants to preserve his physical life should follow the living state of infancy. In the final analysis, this state of being embodies the way of naturalness and freedom from desires.
With regard to the material and bodily pleasure-seeking phenomena and related problems that we encounter nowadays, we can profit from Lao Zi's instruction: "The desire to multiply life's enjoyments means ill omen; the mind to employ qi excessively suffers fatal stiffness."

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