(Lord Ramachandra killing the demon Ravana—click to enlarge)
"Although a responsible man in the administration of a state is required to be saintly, he should not be cowardly. For example, Lord Rāma was so saintly that people even now are anxious to live in the kingdom of Lord Rāma (rāma-rājya), but Lord Rāma never showed any cowardice. Rāvaṇa was an aggressor against Rāma because Rāvaṇa kidnapped Rāma's wife, Sītā, but Lord Rāma gave him sufficient lessons, unparalleled in the history of the world."
(Bhagavad-gītā As It Is 1.36, Purport)
"Rāvaṇa was made a very powerful man by worshiping Lord Śiva, and he used to offer severed heads to please Lord Śiva. He became so powerful by the grace of Lord Śiva that all the demigods were afraid of him, until he at last challenged the Personality of Godhead Śrī Rāmacandra and thus ruined himself."
(Śrīmad-Bhāgavatam 2.3.2-7, Purport)
"A cobra is very fierce before ordinary persons, but before an enchanter who can play with him, he is a plaything. Similarly, a demon may be very powerful in his own domain, but before the Lord he is insignificant. The demon Rāvaṇa was a fierce figure before the demigods, but when he was before Lord Rāmacandra he trembled and prayed to his deity, Lord Śiva, but to no avail."
(Śrīmad-Bhāgavatam 3.18.13, Purport)
"There is a saying that when Kṛṣṇa protects someone, no one can do him harm, and when Kṛṣṇa wants to kill someone, no one can protect him. The vivid example was Rāvaṇa. Rāvaṇa was a great devotee of Lord Śiva, but when Lord Rāmacandra wanted to kill him, Lord Śiva could not protect him. If some demigod, even Lord Śiva or Lord Brahmā, wants to do harm to a devotee, Kṛṣṇa protects the devotee. But when Kṛṣṇa wants to kill someone, such as Rāvaṇa or Hiraṇyakaśipu, no demigod can protect him."
(Śrīmad-Bhāgavatam 4.7.47, Purport)
"People in the material world are very fond of the goddess of fortune, and they want her favor in the form of riches. They should know, however, that the goddess of fortune is inseparable from Lord Viṣṇu. Materialists should understand that the goddess of fortune should be worshiped along with Lord Viṣṇu and should not be regarded separately. Materialists seeking the favor of the goddess of fortune must worship Lord Viṣṇu and Lakṣmī together to maintain material opulence. If a materialist follows the policy of Rāvaṇa, who wanted to separate Sītā from Lord Rāmacandra, the process of separation will vanquish him. Those who are very rich and have taken favor of the goddess of fortune in this world must engage their money in the service of the Lord. In this way they can continue in their opulent position without disturbance."
(Śrīmad-Bhāgavatam 4.15.3, Purport)
"By the grace of Lord Śiva, a devotee gets the opportunity to be blessed by the goddess Durgā. Rāvaṇa, for example, was a great worshiper and devotee of Lord Śiva, and in return he got all the blessings of goddess Durgā, so much so that his whole kingdom was constructed of golden buildings. In Brazil, in this present age, huge quantities of gold have been found, and from historical references in the Purāṇas, we can guess safely that this was Rāvaṇa's kingdom. This kingdom was, however, destroyed by Lord Rāmacandra.
"By studying such incidents, we can understand the full meaning of īśa-vidhvaṁsitāśiṣām. The Lord does not bestow material blessings upon the devotees, for they may be entrapped again in this material world by continuous birth, death, old age and disease. Due to materialistic opulences, persons like Rāvaṇa become puffed up for sense gratification. Rāvaṇa even dared kidnap Sītā, who was both the wife of Lord Rāmacandra and the goddess of fortune, thinking that he would be able to enjoy the pleasure potency of the Lord. But actually, by such action, Rāvaṇa became vidhvaṁsita, or ruined. At the present moment human civilization is too much attached to economic development and sense gratification and is therefore nearing the path of ruination."
(Śrīmad-Bhāgavatam 4.22.36, Purport)
"Riches come from Lakṣmī, the goddess of fortune, and the goddess of fortune is the property of Nārāyaṇa, the Supreme Personality of Godhead. The goddess of fortune cannot stay anywhere but by the side of Nārāyaṇa; therefore another of her names is Cañcalā, restless. She cannot be peaceful unless she is in the company of her husband, Nārāyaṇa. For example, Lakṣmī was carried away by the materialistic Rāvaṇa. Rāvaṇa kidnapped Sītā, the goddess of fortune belonging to Lord Rāma. As a result, Rāvaṇa's entire family, opulence and kingdom were smashed, and Sītā, the goddess of fortune, was recovered from his clutches and reunited with Lord Rāma. Thus all property, riches and wealth belong to Kṛṣṇa."
(Śrīmad-Bhāgavatam 5.14.24, Purport)
"Although Rāvaṇa tried to abduct the goddess of fortune Sītādevī from the custody of Lord Rāmacandra, he could not possibly do so. The Sītādevī he forcibly took with him was not the original Sītādevī, but an expansion of māyā, or Durgādevī. As a result, instead of winning the favor of the real goddess of fortune, Rāvaṇa and his whole family were vanquished by the power of Durgādevī."
(Śrīmad-Bhāgavatam 5.18.22, Purport)
"Unless one is saturated with love for the Supreme Personality of Godhead, one cannot appreciate the transcendental value of Lord Rāmacandra; one cannot see Him with material eyes. Because demons like Rāvaṇa have no spiritual vision, they consider Lord Rāmacandra an ordinary kṣatriya king. Rāvaṇa therefore attempted to kidnap Lord Rāmacandra's eternal consort, Sītādevī. Actually, however, Rāvaṇa could not carry off Sītādevī in her original form. As soon as she was touched by Rāvaṇa's hands, she gave him a material form, but she maintained her original form beyond his vision. Therefore in this verse the words pratyak praśāntam indicate that Lord Rāmacandra and His potency, the goddess Sītā, keep themselves aloof from the influence of the material energy."
(Śrīmad-Bhāgavatam 5.19.4, Purport)
"Na ca daivāt paraṁ balam: no one can surpass the strength of the Transcendence. Rāvaṇa was so sinful and shameless that he did not know what the result would be of kidnapping mother Sītā, the pleasure potency of Rāmacandra. This is the disqualification of the Rākṣasas. Asatyam apratiṣṭhaṁ te jagad āhur anīśvaram (BG 16.8). The Rākṣasas are unaware that the Supreme Lord is the ruler of the creation. They think that everything has come about by chance or accident and that there is no ruler, king or controller. Therefore the Rākṣasas act independently, as they like, going even so far as to kidnap the goddess of fortune. This policy of Rāvaṇa's is extremely dangerous for the materialist; indeed, it brings ruin to the materialistic civilization. Nonetheless, because atheists are Rākṣasas, they dare to do things that are most abominable, and thus they are punished without fail. Religion consists of the orders of the Supreme Lord, and one who carries out these orders is religious. One who fails to carry out the Lord's orders is irreligious, and he is to be punished."
(Śrīmad-Bhāgavatam 9.10.22, Purport)