The construction of the Temple requires a specific national environment. The period of peace and security from enemies is not merely a historical reality, but a necessary precondition for building the Temple [מלבי״ם]. To inspire the people, the speaker reminds them that God is actively present with them [מצודת דוד]. It is God Himself who has granted them true rest from all their surrounding enemies [ביאור שטיינזלץ].
As a direct result of this divine support, the land was successfully captured and conquered [מצודת דוד]. This victory took place before God and His people, reflecting a clear recognition that the entire conquest was achieved solely through His help and by the efforts of His nation [מצודת דוד].