Vidura was confident about this (although junior by age, Uddhava was much advanced in the devotional service of the Lord), and thus he addressed Uddhava in that higher category. That is the way of courteous dealings between two devotees

Expressions researched:
"Vidura was confident about this, and thus he addressed Uddhava in that higher category. That is the way of courteous dealings between two devotees"

Srimad-Bhagavatam

SB Canto 3

But although junior by age, Uddhava was much advanced in the devotional service of the Lord, and therefore he is described herein as the chief amongst the devotees of the Lord. Vidura was confident about this, and thus he addressed Uddhava in that higher category. That is the way of courteous dealings between two devotees.

SB 3.4.24, Translation and Purport

While Uddhava, the chief and most confidential amongst the devotees of the Lord, was going away, Vidura, in affection and confidence, questioned him.

Vidura was much older than Uddhava. By family relationship Uddhava was a contemporary brother of Kṛṣṇa's, while Vidura was as elderly as Kṛṣṇa's father Vasudeva. But although junior by age, Uddhava was much advanced in the devotional service of the Lord, and therefore he is described herein as the chief amongst the devotees of the Lord. Vidura was confident about this, and thus he addressed Uddhava in that higher category. That is the way of courteous dealings between two devotees.