'Steadfastness' in the Bible

constantly bearing in mind your work of faith and labor of love and steadfastness of hope in our Lord Jesus Christ in the presence of our God and Father,

But now that Timothy has come back to us from [his visit with] you, and has brought us good news of your [steadfast] faith and [the warmth of your] love, and [reported] that you always think kindly of us and treasure your memories of us, longing to see us just as we long to see you,