God's Challenge: Prepare for Worse Trials

Jeremiah 12:5-6

If thou hast been wearied with running with footmen, how canst thou contend with horses? and if thou hast been secure in a land of peace, what wilt thou do in the swelling of the Jordan?

For even thy brethren, and the house of thy father, even they have fought against thee, and have cried after thee with full voice: believe them not when they speak good things to thee.