Pratipūrṇa-bhāṣīṇīm (“speaking everything that was appropriate for an uninvited guest”) indicates that Sītā-devī told him that everything was ready [to receive him as an uninvited guest].

NOTE. As a general principle, it is an important duty of gṛhasthas and their wives to appropriately honor uninvited guests.

In Śrīmad-Bhāgavatam (8.16.6-7), Kaśyapa speaks to his wife Aditi about this duty:

api vātithayo ’bhyetya kuṭumbāsaktayā tvayā
gṛhād apūjitā yātāḥ pratyutthānena vā kvacit

“I wonder whether because of being too attached to the members of your family, you failed to properly receive uninvited guests, who therefore were not welcomed and went away.”

gṛheṣu yeṣv atithayo nārcitāḥ salilair api
yadi niryānti te nūnaṁ pherurāja-gṛhopamāḥ

“Homes from which guests go away without having been received even with an offering of a little water are like those holes in the field which are the homes of jackals.”

Prabhupāda’s purports to these two verses clarify this subject:

It is the duty of a householder to receive guests, even if a guest be an enemy. When a guest comes to one’s home, one should properly receive him by standing up and offering him a seat. It is enjoined, gṛhe śatrum api prāptaṁ viśvastam akutobhayam: if even an enemy comes to one’s home, one should receive him in such a way that the guest will forget that his host is an enemy. According to one’s position, one should properly receive anyone who comes to one’s home. At least a seat and a glass of water should be offered, so that the guest will not be displeased. Kaśyapa Muni inquired from Aditi whether disrespect had been shown to such guests, or atithis. The word atithi refers to one who comes without an invitation.

In a field there may be holes made by snakes and mice, but when there are very big holes, it may be supposed that jackals live there. Certainly no one goes to take shelter in such homes. Thus the homes of human beings where atithis, uninvited guests, are not properly received are like the homes of jackals.

In this Rāmāyaṇa verse, svātmavadhāya (“just to kill himself”) is an idiomatic way of saying, “as a consequence of which he would surely cause his own death.”

Apart from the death of one’s body that can come about due to unrestrained lust, there are other consequences one has to face when he tries to satisfy his lust:

One tries to satisfy his lust, and when he cannot, anger and greed arise. A sane man who does not want to glide down to the species of demoniac life must try to give up these three enemies, which can kill the self to such an extent that there will be no possibility of liberation from this material entanglement. (Bhagavad-gītā 16.21 purport)

In Śrīmad-Bhāgavatam 11.10.27-29, Lord Kṛṣṇa informs Uddhava of the result of pursuing his lust beyond the confines of Vedic dharma in this manner:

yady adharma-rataḥ saṅgād asatāṁ vājitendriyaḥ
kāmātmā kṛpaṇo lubdhaḥ straiṇo bhūta-vihiṁsakaḥ

paśūn avidhinālabhya preta-bhūta-gaṇān yajan
narakān avaśo jantur gatvā yāty ulbaṇaṁ tamaḥ

karmāṇi duḥkhodarkāṇi kurvan dehena taiḥ punaḥ
deham ābhajate tatra kiṁ sukhaṁ martya-dharmiṇaḥ

“If a human being is engaged in sinful, irreligious activities, either because of bad association or because of his failure to control his senses, then such a person will certainly develop a personality full of material desires. He thus becomes miserly toward others, greedy and always anxious to exploit the bodies of women. When the mind is so polluted one becomes violent and aggressive and without the authority of Vedic injunctions slaughters innocent animals for sense gratification. Worshiping ghosts and spirits, the bewildered person falls fully into the grip of unauthorized activities and thus goes to hell, where he receives a material body infected by the darkest modes of nature. In such a degraded body, he unfortunately continues to perform inauspicious activities that greatly increase his future unhappiness, and therefore he again accepts a similar material body. What possible happiness can there be for one who engages in activities inevitably terminating in death?”