Valmiki Ramayana Ayodhya Kanda Sarga 21 Shloka 38
Original Shlokaतव लक्ष्मण जानामि मयि स्नेहमनुत्तमम्। विक्रमं चैव सत्त्वं च तेजश्च सुदुरासदम्।।2.21.38।।
1 source checked for this shloka
लक्ष्मण O Lakshmana, तव your, मयि in me, अनुत्तमम् exceedingly great, स्नेहम् affection, विक्रमं चैव also valour, सत्त्वं च also strength, सुदुरासदम् unassailable, तेजश्च energy, जानामि I know.
I know, O Lakshmana, your profound affection for me. I also know your valour, strength and unassailable energy.