Valmiki Ramayana Sundara Kanda Sarga 16 Shloka 3
Original Shlokaमान्या गुरुविनीतस्य लक्ष्मणस्य गुरुप्रिया। यदि सीताऽऽपि दुःखार्ता कालो हि दुरतिक्रमः।।5.16.3।।
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गुरुविनीतस्य welltrained, लक्ष्मणस्य Lakshmana's, मान्या worshipped, गुरुप्रिया loved by elders, सीतापि Sita too, दुःखार्ता यदि if she is also worried like this, कालः time, दुरतिक्रमः हि difficult to transgress.
"If Sita, who is worshipped by righteous Lakshmana and loved by Rama is tortured like this, it shows it is difficult to trangress the force of time.