The foundation of spiritual and practical leadership demands a continuous connection to the word of God. The guidance given to Joshua serves as a timeless compass, weaving together constant study, deep reflection, and careful action as the absolute formula for success and wisdom. This directive focuses on a specific scroll, referring either to the Book of Deuteronomy that was physically placed before him [רש״י], or more broadly to the complete set of Commandments transmitted by Moses [מצודת דוד, ביאור שטיינזלץ]. The requirement is that these teachings must never be removed or distanced from him [מצודת ציון, ביאור שטיינזלץ].
The primary approach among commentators is that this instruction is a binding command. However, some view it as a divine blessing. In this light, God promises Joshua that even though he will be consumed by the heavy burdens of leading the people, He will grant him special success to remain deeply connected to the teachings without ever abandoning them [רד״ק, ביאור שטיינזלץ].
The expected method of study involves both verbal expression and internal thought [מצודת ציון, ביאור שטיינזלץ]. Some commentators identify a division into distinct study techniques. Keeping the words constantly on one's lips points to the continuous repetition and learning of practical laws. At the same time, the demand to meditate on them requires deep intellectual focus and heartfelt logic regarding the theoretical aspects of the law [רש״י, מלבי״ם]. Another perspective suggests that the initial focus points to the Written Law, while the subsequent call for meditation refers to the Oral Law, which necessitates both speech and active thought [חומת אנך]. Practically, the requirement to engage in this study throughout the day and night means a person must utilize any free time that remains after attending to the work necessary to earn a livelihood [רד״ק].
The ultimate purpose of this constant engagement is practical application. If the teachings cease to be spoken, there is a real danger that a person might forget the Commandments [מצודת דוד]. Furthermore, deep study leads a person to discover that the details of the Oral Law are actually recorded and hinted at within the Written Law, which strengthens the commitment to fulfill them perfectly [מלבי״ם, אלשיך]. This continuous study also resolves a spiritual challenge. Since a single individual cannot physically fulfill all of the Commandments, the very act of frequent reading and studying is credited as if the person had practically observed everything written [חומת אנך].
The result of this dedication is twofold, bringing both success and a sharpened intellect. While some interpret these two concepts as synonyms expressing general prosperity and success [רד״ק], others draw a clear distinction between them. Success refers to divine assistance, good fortune, and prosperity in material and worldly affairs, whereas a sharpened intellect describes an internal ability to choose the right path in spiritual matters and know how to act correctly [מלבי״ם, ביאור שטיינזלץ]. According to another approach, success is manifested in understanding the teachings truthfully without any deviation, while the sharpened intellect is expressed practically through the conquest of the land and the physical fulfillment of the Commandments [אלשיך].