One of the Sanskrit shlokas that PM Modi recited is from the Mahasubhasitasamgraha, a collection of Sanskrit aphorisms collected from various sources. Unfortunately, the search results do not provide the specific shloka that PM Modi recited. However, it is worth noting that PM Modi has tweeted in Sanskrit before and has also used Sanskrit slogans in his speeches. For example, during his presidency of the Group of 20, he chose the Sanskrit term "Vasudhaiva Kutumbakam" as his theme, which means "the world is one family". Therefore, it is possible that the shloka PM Modi recited was related to the theme of collective strength or unity, which he often emphasizes in his speeches.