How authentic is the Hadith: "Death is the believer's gift"? And what is its explanation?

The hadith is weak when attributed to the Prophet (marfu‘an), but it is acceptable when attributed to Ibn Mas‘ud (mawqufan). Its meaning is that death is a gift for the believer because it liberates him from the trials and tribulations of this world, and leads him to eternal life and everlasting happiness in Paradise. Death is a second birth and a transition from the transient abode to the everlasting abode. However, this does not mean that one should wish for death, as life for a believer is an increase in obedience and reward.