# for a little while

"for a short time"

# the God of all grace

"the God who always gives us what we need" or "the God who is always gracious".

# who called you to his eternal glory in Christ

"who chose you to share his eternal glory in heaven because you are joined to Christ"

# perfect you

"make you perfect" or "restore you" or "make you well again"

# confirm you, strengthen you

God will enable the believers to trust in him and to obey him regardless of any suffering they may experience.