Ramayana
मा शुचः पुरुषव्याघ्र कालस्य गतिरीदृशी । त्वद्विधा न हि शोचन्ति बुद्धिमन्तो मनस्विनः ॥ 7-52-10 ॥
"Do not grieve, O tiger among men; such is the course of time. Men like you, who are wise and resolute of mind, do not lament."
english translation