Because he knew of Jehovah’s feelings. Jehovah would “have a yearning ” to see his faithful servant again.
وَكَانَ هذَا ٱلتَّحَرُّرُ وَاقِعًا أَكِيدًا بِٱلنِّسْبَةِ إِلَيْهِ وَأَدْرَكَ أَنَّ ٱلْفَرَجَ سَيَأْتِي لَا مَحَالَةَ .‏