Valmiki Ramayana Sundara Kanda Sarga 28 Shloka 4
Original Shlokaसुखाद्विहीनं बहुदुःखपूर्ण मिदं तु नूनं हृदयं स्थिरं मे। विशीर्यते यन्न सहस्रधाऽद्य वज्राहतं शृङ्गमिवाचलस्य।।5.28.4।।
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सुखात् of joy, विहीनम् devoid, बहुदुःखपूर्णम् filled with agony, इदम् this, मे my, हृदयम् heart, नूनम् surely, स्थिरम् hard, यत् such, वज्राहतम् hit by a thunderbolt, अचलस्य of a mountain, शृङ्गमिव like the top, सहस्रधा into a thousand pieces, अद्य now, न विशीर्यते it is not breaking.
"Even though I am devoid of joy, and living in deep agony, my heart bursts not into a thousand pieces like the summit of a mountain hit by thunderbolt (lightning).