Have you read ALL of the New Testament?
Philippians 4
4Rejoice in the Lord always. I will say it again: Rejoice!
5Let your gentleness be evident to all. The Lord is near.
6Do not be anxious about anything, but in every situation, by prayer and petition, with thanksgiving, present your requests to God.
7And the peace of God, which transcends all understanding, will guard your hearts and your minds in Christ Jesus.
8Finally, brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things.
9Whatever you have learned or received or heard from me, or seen in me—put it into practice. And the God of peace will be with you.
Romans 5
1Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ,
2through whom we have gained access by faith into this grace in which we now stand. And we boast in the hope of the glory of God.
3Not only so, but we also glory in our sufferings, because we know that suffering produces perseverance;
4perseverance, character; and character, hope.
5And hope does not put us to shame, because God’s love has been poured out into our hearts through the Holy Spirit, who has been given to us.
James 1
2Consider it pure joy, my brothers and sisters, whenever you face trials of many kinds,
3because you know that the testing of your faith produces perseverance.
4Let perseverance finish its work so that you may be mature and complete, not lacking anything.
Christians take heart because of God's promises:
Deuteronomy 31
8 The LORD himself goes before you and will be with you; he will never leave you nor forsake you. Do not be afraid; do not be discouraged.