It is important to check root words when looking into the Greek behind a word in Scripture. Any time one looks into the Greek it becomes a continuing study.
In the Greek, Christ was claiming to be Yahweh God when he said, “this is my body” and “this is my blood” in Matthew 26:26. The word translated “is” is esti a third person singular present indicative of G1510. G1510 is eimi and has the embedded meaning of “I exist”, or “I AM”.
The Greek eimi is also found buried in the word power or authority in Romans 13:1 indicating that the subject is Law based only on the I AM, not man’s law.