Cardinal John Henry Newman (1801-1890) wrote:

God has created me
to do Him some definite service.
He has committed some work to me
which He has not committed to another.
I have my mission.
I may not know what it is in this life.
But I shall be told in the next.
I am a link in a chain,
a bond of connection between persons.
He has not created me for nothing.
I shall do good. I shall do His work.
Therefore I will trust Him.
Whatever I do, wherever I am, I cannot be thrown away.
If I am in sickness, my sickness may serve Him.
If I am in sorrow, my sorrow may serve Him.
He does nothing in vain. He knows what He is about.