Q. Why do we say the three words, E-l Melech Ne’eman, before the Shema?
The idea is that the whole of our person attests to the existence and oneness of the Almighty (the Psalmist says, Kol atz’motai tomarna – “All my bones declare, ‘Lord, who is like You?'”: Psalm 35:10).
This arithmetical calculation explains why the three words are left out in congregational worship, when the officiant adds three words at the end – HaShem Elokechem Emet, also adding up to 248.
The three words E-l Melech Ne’eman can also be taken as symbols of the three tenses – past, present and future.
Before the world’s creation, HaShem was E-l, the powerful One, but He was all alone. When the world was brought into being, He became Melech, the King: now He had a kingdom. As Ne’eman, the faithful One, He will lead and preserve His world and bring about the final redemption.