What is a Christian? Christians can be described from many angles, but from what we have said it is clear that we can cover everything by saying: True Christians are people who acknowledge and live under the word of God. They submit without reserve to the word of God written in “the Book of Truth” (Dan 10:21), believing the teaching, trusting the promises, following the commands. Their eyes are upon the God of the Bible as their Father and the Christ of the Bible as their Savior.
Christians will tell you, if you ask them, that the Word of God has both convinced them of sin and assured them of forgiveness. Their consciences, like Luther’s, are captive to the Word of God, and they aspire, like the psalmist, to have their whole lives brought into line with it. “Oh, that my ways were steadfast in obeying your decrees!” “Do not let me stray from your commands.” “Teach my your decrees. Let me understand the teaching of your precepts.” “Turn my heart toward your statutes.” ” May my heart be blameless toward your decrees” (Ps 119:5, 10, 26-27, 36, 80). The promises are before them as they pray, and the precepts are before them as they go about their daily tasks.

-J.I. Packer, Knowing God, pg 116

God’s wisdom is not, and never was, pledged to keep a fallen world happy, or to make ungodliness comfortable. Not even to Christians has he promised a trouble-free life; rather the reverse. He has other ends in view for life in this world than simply to make it easy for everyone.

What is he after, then? What is his goal? What does he aim at? When he made us, his purpose was that we should love and honor him, praising him for the wonderfully ordered complexity and variety of his world, using it according to his will, and so enjoying both it and him. And though we have fallen, God has not abandoned his first purpose. Still he plans that a great host of humankind should come to love and honor him. His ultimate objective is to bring them to a state in which they please him entirely and praise him adequately, a state in which he is all in all to them and he and they rejoice continually in the knowledge of each other’s love–people rejoicing in the saving love of God, set upon them from all eternity, and God rejoicing in the responsive love of people, drawn out of them by grace through the gospel.

-J.I. Packer, Knowing God, pg 91-92