Bhagavad Gita 10.33

अक्षराणामकारोऽस्मि द्वन्द्वः सामासिकस्य च।अहमेवाक्षयः कालो धाताऽहं विश्वतोमुखः ॥१०.३३॥

akṣarāṇāmakāro’smi dvandvaḥ sāmāsikasya caahamevākṣayaḥ kālo dhātā’haṃ viśvatomukhaḥ

Among the letters of the alphabet, I am the letter 'A' and the dual among compounds. I am verily the inexhaustible and everlasting time; I am the dispenser of the fruits of actions, having faces in all directions.

गीता