There are two basic restrictions on marriage in the Bible: Number one, she should marry a man. Number two, he should be a Christian.
John PiperThe suffering of sickness and the suffering of persecution have this in common: they are both intended by Satan for the destruction of our faith, and governed by God for the purifying of our faith... Christ sovereignly accomplishes His loving, purifying purpose, by overruling Satan's destructive attempts. Satan is always aiming to destroy our faith; but Christ magnifies His power in weakness.
John PiperIf at the cross every sin was covered, Satan's mouth is shut. He has no weapon. He can gum you but his fangs are gone.
John PiperEvery Christian who struggles with depression struggles to keep their hope clear. There is nothing wrong with the object of their hope - Jesus Christ is not defective in any way whatsoever. But the view from the struggling Christian's heart of their objective hope could be obscured by disease and pain, the pressures of life, and by Satanic fiery darts shot against them... All discouragement and depression is related to the obscuring of our hope, and we need to get those clouds out of the way and fight like crazy to see clearly how precious Christ is.
John Piper