Monotheism doesn’t deny Christ who has already come to give eternal life to whosoever believes on him.
But to argue for a monotheistic God of apostate Jews as you do, is a denial that Jesus Christ, the Son of God is GOD Who has come to mankind in the flesh also denies the Spirit of God in us is of God. God alone gives eternal life through His Spirit to all who believe in His Son. Without the three who could be eternally saved? You clearly understand this truth but still you continue to argue for the monotheistic God of apostate Jews who argue for ONE God and deny He is Christ Jesus our Lord.