God's purpose.

And we know that for those who love God all things work together for good, for those who are called according to His purpose. For those whom He foreknew He also predestined to be conformed to the image of His Son. -Romans 8:28-29

God is concerned with His purpose - to make His people holy like His Son and thus glorify Himself. He is sovereign over all things and He will do whatever it takes large or small, exciting or life-devastating, exalting or humbling to do so.

There are times when it costs us everything in this world but surely it is a great mercy in comparison to "the glory that is to be revealed to us" in the life to come. If we are His, no matter how terrible our situations may get, we can be assured that He is doing it all for our good.

For what will it profit a man if he gains the whole world and forfeits his soul? Or what shall a man give in return for his soul? -Matthew 16:26

God moves in a mysterious way
His wonders to perform;
He plants His footsteps in the sea
And rides upon the storm.

Deep in unfathomable mines
Of never failing skill
He treasures up His bright designs
And works His sovereign will.

Ye fearful saints, fresh courage take;
The clouds ye so much dread
Are big with mercy and shall break
In blessings on your head.

Judge not the Lord by feeble sense,
But trust Him for His grace;
Behind a frowning providence
He hides a smiling face.

His purposes will ripen fast,
Unfolding every hour;
The bud may have a bitter taste,
But sweet will be the flower.

Blind unbelief is sure to err
And scan His work in vain;
God is His own interpreter,
And He will make it plain.

-God Moves in a Mysterious Way, William Cowper