Valmiki Ramayana Ayodhya Kanda Sarga 20 Shloka 26
Original Shlokaस स्वभावविनीतश्च गौरवाच्च तदा नतः। प्रस्थितो दण्डकारण्यमाप्रष्टुमुपचक्रमे।।2.20.26।।
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स्वभावविनीतश्च by nature modest, तदा then, गौरवात् out of reverence (for his mother), नतः च humble also, सः he, दण्डकारण्यम् to Dandaka forest, प्रस्थितः for his departure, अप्रष्टुम् to seek her permission, उपचक्रमे commenced.
Modest by nature, Rama with respectful humility began seeking her permission for his departure to Dandaka forest: