There is not human who can be called "a manifestation of God" since humans are born babies. There are not babies-God, like people use to say when they refer to that baby they put on the christmas tree: "baby-God". Really?
So there are not humans that can be called "a manifestation of God". BTW, the real God cann't be seen by humans, which is easy to understand if you consider that He was the Creator of the Universe.
Our sense organs have a very limited spectrum of perception, because we were created to live on the physical earthly plane. In any case, what we can have is a messenger from God like the prophets, and ultimately Jesus, His own First Born and Only-Begotten Son:
John 1:14 So the Word became flesh and resided among us, and we had a view of his glory, a glory such as belongs to an only-begotten son from a father; and he was full of divine favor and truth.
... 3:1 ... Nicodemus, a ruler of the Jews. 2 This one came to him in the night and said to him: “Rabbi, we know that you have come from God as a teacher, for no one can perform these signs that you perform unless God is with him.”
Acts 2:22 Men of Israel, hear these words: Jesus the Nazarene was a man publicly shown to you by God through powerful works and wonders and signs that God did through him in your midst, just as you yourselves know.
... 10:38 about Jesus who was from Nazareth, how God anointed him with holy spirit and power, and he went through the land doing good and healing all those oppressed by the Devil, because God was with him.