Bhagavad Gita · 4.5

श्रीभगवानुवाचबहूनि मे व्यतीतानि जन्मानि तव चार्जुन।तान्यहं वेद सर्वाणि न त्वं वेत्थ परन्तप॥

śhrī bhagavān uvācha bahūni me vyatītāni janmāni tava chārjuna tāny ahaṁ veda sarvāṇi na tvaṁ vettha parantapa

The Supreme Lord said: Both you and I have had many births, O Arjuna. I remember them all, but you do not, O scorcher of foes.

— Bhagavad Gita 4.5

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)