It is really not quite accurate to call One Perfect Life: The Complete Story of the Lord Jesus by John MacArthur a harmony of the gospels. Though the book, using the text of Matthew as its base, does provide a harmony of the gospels, it does so in a very unique way — by blending the separate accounts into one continuous narrative, including details from all four gospels (without repeating parallel statements).
More interestingly, the blending includes Scriptural accounts from the New King James Version of New and Old Testaments. For example,
GEN In the beginning God created the heavens and the earth. JN In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things were made through Him, and without Him nothing was made that was made.
1COR There is one God, the Father, of whom are all things, and we for Him; and one Lord Jesus Christ, through whom are all things, and through whom we live, HEB whom He has appointed heir of all things, through whom also He made the worlds; who being the brightness of His glory and the express image of His person, and upholding all things by the word of His power, COL is the image of the invisible God, the firstborn over all creation.
If you are looking for the perfect family read-aloud to celebrate Easter, check out One Perfect Life, currently only $2.99 for the Kindle version (readable on other devices).
The objective is to bring into full view the One who is Immanuel, God with us, the Eternal Word made flesh, the preexistent, coexistent, self-existent Son of God who became the Son of Man to die and rise again for our salvation.