GenApoc 6.12 :וטמרת רזא דן בלבבי ולכול אנוש לא אחויתה‏ : I hid this secret in my heart and did not reveal it to anyone
See the entire entry for ṭmr vb. to hide or bury s.t. in the ground

GenApoc 6.12 :וטמרת רזא דן בלבבי‏ : but I hid this secret in my heart
See the entire entry for rāz, rāzā n.m. mystery