When someone transitions from life to death, their soul remains in the body and the spirit leaves. The spirit has only two options, either to remain in the body so that the person remains alive, or to leave. If the spirit leaves the body, its destination generally is heaven or hell, but it also can remain in the earth realm. Those marked and destined for heaven are immediately transported to heaven accompanied by angelic guides. Being on the earth for longer than twenty-four hours after the transition is a sign that the spirit is unable to gain access to heaven.
There are several reasons why a spirit may be unable to gain access to heaven. If the spirit is a child under the age of twelve, they are instantly transported to heaven by angelic guides. However, an older child who has not engaged in immorality may be unable to gain access because their solar plexus has become contaminated as a result of infiltration by evil spirits. The solar plexus can easily be contaminated if the child lives in an area with significant amounts of demonic activity.
If the spirit is an adult, they may be unable to gain access to heaven for one major reason--sin. Sin of every kind contaminates and weakens the spirit, so it remains in the earth and waits to be rescued. A rescue by heaven happens only when the person has the indwelling Holy Spirit which marks them as belonging to God. Thus, during the seven-day period after they transition, someone would have to pray for them to receive the Holy Spirit. When the Holy Spirit enters them, a light will appear, and they instantly will be transported to the third heaven. If they are not marked with the indwelling Holy Spirit, hell can take possession of their spirit.
In the past, hell sought to take instant possession of an unmarked spirit. Now, the Lord God Almighty has determined that hell must wait until the expiration of seven days prior to doing so. In the interim period, other than giving the person the indwelling Holy Spirit, if someone prays for them, it is likely that their spirit might be sufficiently strengthened to enable them to enter the first heaven, especially if the person has not committed sexual immorality.
All saints day which is celebrated by many Christians is a day on which every person should examine their lives and cleanse their spirits through repentance and forgiveness in order to strengthen it. The Jewish Yom Kippur, a day of atonement has a similar purpose. This once a year cleansing is in addition to the daily examination and spiritual cleansing that should take place in every person. When all has been said and done, spiritual fitness is equally as important as physical fitness.