Bhagavad Gita 4.7

यदा यदा हि धर्मस्य ग्लानिर्भवति भारत।अभ्युत्थानमधर्मस्य तदाऽऽत्मानं सृजाम्यहम्॥

yadā yadā hi dharmasya glānirbhavati bhārata |abhyutthānamadharmasya tadā''tmānaṃ sṛjāmyaham ||

Whenever there is a decline of righteousness and an increase of unrighteousness, O Arjuna, then I manifest Myself.

Whenever spirituality decays and materialism is rampant, then, O Arjuna, I reincarnate myself.

Our plain-language meaning of this verse is waiting for scholar review.