It is your philosophy that is tormenting you, not your theology ...

"With all my heart I hate those cares by which you state that you  are consumed. 

They rule your heart, not account of the greatness of the cause but by reason of the greatness of your unbelief.

The same cause existed in the time of John Hus and many others, and they had a harder time of it than we do.

Great though our cause is, its Author and Champion is also great, for the cause is not ours.

Why, then, are you constantly tormenting yourself? 

If our cause is false, let us recant.

But if it is true, why should we make Him a liar who has given us such great promises and who commands us to be confident and undismayed? ‘Cast thy burden upon the Lord,’ (Ps. 55:11) says he. ‘The Lord is nigh unto all them that call upon him.’ (Ps 145:18).

Does he speak like this for nothing, or to beasts?

It is your philosophy that is tormenting you, not your theology …

What good to you expect to accomplish by these vain worries of yours?

What can the devil do more than slay us?  Yes, what?

I beg you, who are so pugnacious in everything else, fight against yourself, your own worst enemy, for you furnish Satan with too many weapons against yourself.

Christ died once for our sins. He will not die again for truth and just, but will live and reign. 

If this be true, and if he reigns, why should you be afraid for the truth?

Perhaps you are afraid that it will be destroyed by God’s wrath.  Even if we should ourselves be destroyed, let it not be by our own hands.

He who is our Father will also be the Father of our children

God, who is able to raise the dead, is also able to uphold his cause
when it is falling, or to raise it up again when it has fallen, or to move it
forward when it is standing.

If we are not worthy instruments to accomplish his purpose, he will
find others.

If we are not strengthened by his promises, where in all the world are
the people to whom these promises apply?"

Martin Luther’s letter to Melanchton

Monday after St. John’s day, 1530

Luther: Letters of Spiritual Counsel

T.G. Tappert  -  p. 146-147