Valmiki Ramayana Kishkindha Kanda Sarga 25 Shloka 4
Original Shlokaनियतिः कारणं लोके नियतिः कर्मसाधनम्। नियतिस्सर्वभूतानां नियोगेष्विह कारणम्4.25.4।।
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लोके the worlds, नियतिः fate, कारणम् cause, नियतिः fate, कर्मसाधनम् to accomplish tasks, इह here, सर्वभूतानाम् for all beings, नियोगेषु to assign respective duties, नियतिः fate, कारणम् is the cause.
'Fate is the cause of the world. Fate is the means of accomplishment. Fate assigns duties to all beings.