In Ayah 4 of Suratul-Hadid Allah said: وَهُوَ مَعَكُمْ أَيْنَ مَا كُنتُمْ (Wa huwa ma^akum aynama kuntum). What does this mean?

This part of the Ayah refers to the fact that Allah has knowledge of us wherever we may be. This meaning was stated by Sufyan ath-Thawriyy, ash-Shafi^iyy, Ahmad, Malik, and others.  Suratut-Talaq Ayah 12 means, “The knowledge of Allah includes everything.” The Prophet said, “You are not calling upon the One Who does not hear or know. In fact you are calling upon the Lord Who hears and knows all.” (Related by al-Bukhariyy.)