avatari narayana, krsna avatara
tenha catur-bhuja, inha manusya-akara
avatari—source of incarnations; narayana—Lord Narayana; krsna—Lord Krsna; avatara—incarnation; tenha—that; catuh-bhuja—four arms; inha—this; manusya—like a man; akara—form.
Because Narayana has four hands whereas Krsna looks just like a man, they say that Narayana is the original God whereas Krsna is but an incarnation.
Link to this page: https://prabhupadabooks.com/cc/adi/61