श्रीभगवान्
In plain words
The Blessed Lord said: Many births of Mine have passed, and many of yours too, Arjuna. I know them all; you do not, scorcher of foes.
Word for word
Many births of Mine have passed, and of yours, O Arjuna; I know them all; you do not know [them], O scorcher of foes.
The commentators
Bhagavadgītābhāṣyam
या वासुदेवे अनीश्वरासर्वज्ञाशङ्का मूर्खाणाम् , तां परिहरन् श्रीभगवानुवाच, यदर्थो ह्यर्जुनस्य प्रश्नः —
बहूनि मे मम व्यतीतानि अतिक्रान्तानि जन्मानि तव च हे अर्जुन । तानि अहं वेद जाने सर्वाणि न त्वं वेत्थ न जानीषे, धर्माधर्मादिप्रतिबद्धज्ञानशक्तित्वात् । अहं पुनः नित्यशुद्धबुद्धमुक्तस्वभावत्वात् अनावरणज्ञानशक्तिरिति वेद अहं हे परन्तप ॥ ५ ॥
In plain words
Fools suspect Vāsudeva of being neither the Lord nor all-knowing. To clear that suspicion away, the Blessed One spoke — and that is exactly what Arjuna's question was for —
"Many of my births have gone by, Arjuna — passed and left behind — and many of yours as well. Every one of them I know. You do not know them, because your power to know is tied down by merit and demerit and everything of that sort. But my nature is eternal, pure, awake, free; nothing is laid over my knowing to screen it. That is how I know, Arjuna, scorcher of foes."
Close to the Sanskrit
Which suspicion of the foolish, regarding Vāsudeva, that he is not the Lord and not all-knowing — dispelling that, the Blessed Lord spoke; for Arjuna's question has that very purpose —
Many, of me — that is, mine — births have gone by, that is, have been passed beyond, and yours too, O Arjuna. Those all I know, that is, I am aware of; you do not know, that is, you are not aware of them, because your power of knowing is fettered by dharma, adharma, and the rest. I, on the other hand, because my very nature is eternal, pure, awake, and free, am one whose power of knowing has no covering over it — thus I know, I, O Parantapa.