In Mark 1:38, Jesus states succinctly the reason why He came from the Father:

“Let us go on to the neighboring towns,
so I may preach there also;
that is why I came.”

J.C. Ryle comments in the late 1800s on this verse from Mark’s Gospel:

Let us never be moved by those who cry down the preacher’s office,
and tell us that sacraments and other ordinances
are of more importance than sermons.
Let us give to every part of God’s public worship
its proper place and honor,
but let us beware of placing any part of it above preaching.
By preaching, the Church of Christ
was first gathered together and founded,
and by preaching, it has ever been maintained in health and prosperity.
By preaching, sinners are awakened.
By preaching, inquirers are led on.
By preaching, saints are built up.
By preaching, Christianity is being carried to a lost world.

There are many now who sneer at missionaries,
and mock at those who go out into the highways of our own land,
to preach to crowds in the open air.
But such persons would do well to pause,
and consider calmly what they are doing.
The very work which they ridicule
is the work which turned the world upside down.

Above all, it is the very work which Christ Himself undertook.
The King of kings and Lord of lords Himself was once a preacher.
For three long years He went to and fro proclaiming the Gospel.
Sometimes we see Him in a house, sometimes on the mountain side,
sometimes in a Jewish synagogue, sometimes in a boat on the sea.
But the great work He took up was always one and the same.
He came always preaching and teaching.
He says, “That is why I have come.”

Let us leave the passage with a solemn resolution
never to “despise prophesying.” (1 Thess. 5:20.)
The minister we hear may not be highly gifted.
The sermons that we listen to may be weak and poor.
But after all, preaching is God’s grand ordinance
for converting and saving souls.
The faithful preacher of the Gospel is handling the very weapon
which the Son of God was not ashamed to employ.
This is the work of which Christ has said, “That is why I have come.”