Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 1: Contents of the Rāmāyaṇa Summarized
Text 1.1.56

पम्पातीरे हनुमता सङ्गतो वानरेण ह।
हनुमद्वचनाच्चैव सुग्रीवेण समागतः॥

pampā-tīre hanumatā saṅgato vānareṇa ha
hanumad-vacanāc caiva sugrīveṇa samāgataḥ

pampā-tīre = on the banks of the river Pampā; hanumatā = Hanumān; saṅgataḥ = He [then] met; vānareṇa ha = the monkey; hanumad-vacanāt ca eva= on the request of Hanumān; sugrīveṇa = Sugrīva; samāgataḥ = He met.

He [then] met the monkey Hanumān on the banks of the river Pampā. On the request of Hanumān, He met Sugrīva.

Canto 3 (Araṇya-kāṇḍa) had primarily pointed out that Lord Rāma was true to His promises. Having summarized the events described in that Canto, from this verse onwards, Nārada Muni summarizes Canto 4 (Kiṣkindhā-kāṇḍa) that describes how to maintain friendship.

Pampā was a lotus pond. The forest on its banks brought about Rāma’s remembrance [of Sītā-devī]. Ha indicates Nārada Muni’s delight [upon Rāma’s meeting Hanumān].1 Vānareṇa hanumatā indicates that Hanumān did not [deceptively] disguise himself the way Rāvaṇa had done; [rather,] he revealed his true identity, indicating that he was trustworthy. And because of Hanumān, Rāma met Sugrīva.

It is implied here that when one gets a favorable mediator, one can attain friendship with a worthy person.

1 Hanumān was sent by Sugrīva whose wife was also stolen.