he present research compares memory, intelligence and personality traits of those adolescents who memorized the Holy book of Muslims, Qur’an (called ‘Hafiz’), and those who did not memorize Holy Qur’an (non-Hafiz). Out of 398 adolescents (16-19 years), 198 were full time students of religious institutions (Madressahs), and 200 were the students of Government run schools. Data were collected from three cities of Pakistan. Three existing measures including Wechsler Memory Scale-4th Edition (WMS-IV) (Wechsler,2009), Sajjad Verbal Intelligence Test in Urdu (SVITU) (Sajjad,2001), and Indigenous Non-Verbal Test of Intelligence (INTI)(Gardezi,2001) were used. WMS-IV was translated, and a Personality Trait Questionnaire (PTQ) (Batool & Gilani,2011) was developed along with establishing its psychometric properties. Results indicated that non-Hafiz group scored higher on all the subscales of WMS-IV except for Verbal Paired Associates subscales (VPA I & II). Hafiz group scored higher on SVITU, and Non-Hafiz group outperformed on INTI and scored higher on warmth, intelligence, emotional stability, excitability, dominance, cheerfulness, sensitivity, and apprehension traits of personality (PTQ). Similarly, Hafiz group scored higher on conformity, boldness, self- sufficiency and self-discipline on the same scale. Gender differences were found on various aspects of memory, verbal and non-verbal intelligence, as well as on personality traits. Unlike non-Hafiz group, males scored higher on WMS-IV in the hafiz group. Likewise, males outperformed females on all subscales of verbal and non-verbal intelligence in Hafiz group. On Personality Trait Questionnaire (PTQ), females scored higher on Sensitivity, and Tension, whereas males score higher on Intelligence, Dominance, Cheerfulness, and Boldness in Hafiz group. Females outperformed males on Intelligence, Conformity, and Tension, whereas males score higher than females on Dominance, Cheerfulness, Boldness, Apprehension in non-Hafiz group. Parents’ education and effect of gender was controlled through MANCOVA analysis and the differences between both the groups were significant on all the scales. Structural Equation Modeling showed significant relationship between memory, intelligence and personality traits. The research suggests that rote memorization, restricted environment, and outdated curriculum are not beneficial for the personality development of growing children.