This verse (chaupai) is from the Balakanda chapter of Shri Ramcharitmanas.

मुद मंगलमय संत समाजू। जो जग जंगम तीरथराजू॥ राम भक्ति जहँ सुरसरि धारा। सरसइ ब्रह्म बिचार प्रचारा॥
This verse (chaupai) is found in Balakanda, describing the company of saints as a form of pilgrimage.
Meaning : The company of saints is filled with joy and brings well-being; it is like a moving, living Prayagraj (the king of holy places) in the world. In this saintly gathering, there is the stream of devotion to Lord Ram, like the sacred Ganges, and the spread of knowledge of the divine, like the Saraswati river.
Context: where this chaupai appears in Shri Ramcharitmanas
In Balkand, Tulsidas ji compares the assembly of saints to Prayag, the king of pilgrimage places. The society of saints is a moving Tirthraj, full of joy and auspiciousness, where devotion to Ram flows like the stream of the Ganga and the discussion of Brahma flows like the Saraswati.
Transliteration
Mud Mangalmay Sant Samaju. Jo Jag Jangam Tirathraju.. Ram Bhakti Jahan Sursari Dhara. Sarasai Brahma Bichar Prachara..
Word meanings
- Mud = joy
- Mangalmay = full of auspiciousness
- Jangam = moving, living
- Tirathraju = king of pilgrimage places (Prayag)
- Sursari = the Ganga
- Sarasai = flows
- Brahma bichar prachara = the spreading discussion of Brahma
As a Shalaka answer
This is an auspicious answer. The question is good and the work will be accomplished, especially if the company and counsel of saintly, good people stays with you, for the very heart of this chaupai is the glory of satsang.