Daniel Rosman's answer correctly identifies the word אמת (emmet) which is the Hebrew word for "truth". However, there is another Hebrew word in the right panel that is written in Latin characters. In the bottom left corner the text says:
... A new shred of the RAGMAN... forever binded by a protective
The word shem is the Hebrew word שם, which means "name". In addition to the simple meaning "name", in certain contexts it can be used specifically to refer to holy or Divine names, that are usually invoked for some supernatural purpose. In Jewish lore you can find protective amulets with such names inscribed on them.
Additionally, the (Hebrew) Wikipedia page for the Jewish name for God says the following (my translation):
בפולקלור היהודי, יודעי תורת הנסתר הפיחו בגולם רוח חיים, על ידי כך שהיו
כותבים את השם המפורש על פיסת נייר, ומניחים אותה בפיו של גוש חומר, ואחר
כך היו רושמים את המילה "אמת" על מצחו. כאשר היה צורך להפסיק את פעולת
הגולם, נמחקה האות א', וכך הוא נותר "מת".
In Jewish Folklore, those who know the Secret Wisdom would blow the breath of life into a
golem by means of writing the Ineffable Name on a piece of paper and placing it in the mouth of a lump of matter, following
which they would write the word אמת [emmet – "truth"] on its
forehead. When it was necessary to stop the operations of the golem
they would erase the letter א [aleph] and what remained would be מת
(Slight explanation – the Hebrew word א-מ-ת is one letter off from the Hebrew word מ-ת. The former means "truth" while the latter is the word for death. Thus by removing the first letter (the א) from the word אמת that was written on the forehead, you would be left with the word מת, signifying that the creature should "die", or shut down.)
Thus, (as mentioned in the other answer) this comic may be referencing the use of the word אמת to activate/deactivate a superpowered creature.
The Hebrew word in the third panel that was edited into the question is the same word: אמת (emmet) – "truth". The slight difference between its appearance here and in the other panels is due to the inclusion of nekudot – dots. Hebrew words can be written with or without nekudot. These dots instruct the reader how to vowelize the word, because the Hebrew alphabet is (for the most part) all consonants. The set of dots under the two letters in this case are segol which tells us that the vowel sound should be "eh". Without the inclusion of the dots the word would technically just say 'mt without telling you that the two syllables both have the "eh" vowelization. Most people familiar with Hebrew would recognize that the letters א-מ-ת are pronounced with the "eh" vowelization, so it is usually not necessary to include the dots.