Why might the Bible demand: “God requireth that which is past”? It can be so alluring to recall memories. What is the harm in that? Three big reasons come to mind: Sentimentality, regret, resentment.
1. Sentimentality - self-absorption, it radiates nothing beneficial to our fellow man, and thus ignores God.
2. Regret - self-absorption, “coulda/shoulda” bondage.
3. Resentment - self-absorption, a hateful state that only leads downward.
God requires these because indulging them enslaves, while releasing them to Love frees.
“God requireth that which is past” does not exclude learning from past mistakes and being grateful for past blessings, because these are progressive, taking us forward instead of backward. “Progress is the law of God, whose law demands of us only what we can certainly fulfil.” (S&H)
The demand to relinquish sentimentality is the most difficult because it can seem pleasant, while the other two are definitely unpleasant! Nonetheless, they are all harmful.
“Rise in the strength of Spirit to resist all that is unlike good. God has made man capable of this and nothing can vitiate the ability and power divinely bestowed upon man.” (S&H)
As though to encourage us in the warfare with oneself, Jesus said, “Fear not, little flock; for it is your Father's good pleasure to give you the kingdom.”
* S&H - Science and Health with Key to the Scriptures by Mary Baker Eddy