तत्क्षेत्रं यच्च यादृक्च यद्विकारि यतश्च यत् |
स च यो यत्प्रभावश्च तत्समासेन मे शृणु || 4||
tat kṣhetraṁ yach cha yādṛik cha yad-vikāri yataśh cha yat
sa cha yo yat-prabhāvaśh cha tat samāsena me śhṛiṇu
BG 13.4: Listen and I will explain to you what that field is and what its nature is. I will also explain how change takes place within it, from what it was created, who the knower of the field of activities is, and what his powers are.