Source: Adi Shankaracharya
अमृतं चैव मृत्युश्च द्वयं देहेप्रतिष्ठितम्।
मोहादुत्पद्यते मृत्युः सत्येनोत्पद्यतेऽमृतम्॥
amṛtaṃ caiva mṛtyuśca dvayaṃ dehepratiṣṭhitam।
mohādupadyate mṛtyuḥ satyenopadyate’mṛtam॥
अमरत्व और मृत्यु दोनों शरीर में निवास करते हैं।
मृत्यु लोभ से आती है और अमरत्व सत्य से।
Immortality and death both reside in the body.
Death comes from temptation and immortality come from the truth.
This shlok from Adi Shankaracharya definitely goes along with the lines ‘अहं ब्रह्मास्मि (ahaṃ brahmāsmi)’ which means ‘I am the infinite reality’. You are a small replica of the universe. In you, there lies immortality and death.
It is upto you to decide which one you want to be. Completely defined by your actions your fate/karma can bring you utter misery or infinite happiness which is referred to here as death and immortality respectively.