All life, said the Puritans, must be managed in such a way that it is sanctified; that is, all activities must be performed, and all experiences received and responded to, in a way that honours God, benefits others as far as possible, and helps us forward in our knowledge and enjoyment of God here as we travel home to the glory of heaven hereafter. Of the experiences to be sanctified, some are pleasant and some are painful. The Puritan labels for the latter are "afflictions" and "crosses"; and bereavement, with the grief it brings, is one such.
How may an experience be sanctified? By relating it to the truth of the gospel, so that we understand it in biblical and evangelical terms; by letting it remind us of truths we might otherwise forget, or not take seriously; and by disciplining our hearts to accept it in an appropriate way - with gratitude or self-humbling or whatever.
From the section "The Sanctifying of Grief" from A Grief Sanctified by JI Packer, pages 187-188.