"No one can have anything unless God gives it"
No one can have life without God.
No one can have health, wealth, wisdom. Riches and all goodness of life unless God gives it.
No one can perform miracles unless God gives it.
Thus, God is the giver of all we have. It is right and just to give thanks to God.
B. He must become more important while I become less important
In this statement John the Baptist knew his purpose.
What was the mission of John.
John said, "I am the voice of someone shouting in the desert: make a straight path for the Lord to travel."
The question is "Do you know your mission."?
If you don't know your purpose, then you will have difficulty to become less important.
The tendency is your Ego will control you.
It says, "I have to become more important."
But John knew His mission to be messenger of God. The time God come, John must become less important so that God can shine and be known to the world that he is the Son of God.
Who come to save us, to rescue us from slavery of sin.
My dear friends let your ego become less important and let your conscience be more important. Vatican II, define conscience as little voice of God.