Twenty second day of Elul
There are said to be 613 mitzvot (commandments) in the bible, though there is some debate as to exactly what they are. The Sefer haChinuch (“Book of Education”) is an anonymous work written in thirteenth-century Spain that details 613 commandments and explains the reasons behind them using biblical texts. There are other formulations too, but whatever one chooses, only one mitzvah can be done without any conscious forethought – that of “Shikhechah” – the mitzvah of forgetting. Based on the verse in Deuteronomy “When you reap the harvest in your field and overlook a sheaf in the field, do not turn back to get it; it shall go to the stranger, the orphan, and the widow—in order that the ETERNAL your God may bless you in all your undertakings.” (Deut 24:19), this is a mitzvah designed to ensure that having left the grain in the field, those people who are following the harvesters to glean what they can from what is left over, are not inconvenienced by the landowner returning. Once he has left the field with his harvest, the remaining “leket” and “peah” belong to the poor.
“To leave what is forgotten to the poor: That we were commanded when we forget a sheaf in the field to leave it there, and that we not return to take it when the thing becomes known to us. And about this is it stated (Deuteronomy 24:19), “and you forget a sheaf in the field […]; it shall go to the stranger, the orphan, and the widow” — meaning to say, leave it there for them.
It is from the roots of the commandment [that it is] since the poor and destitute — in their sin and in their poverty — suspend their eyes upon the produce, in their seeing the owners of the field sheaving their sheaves “according to the blessing of the Eternal that God gave to them”; and they think in their heart, saying, “If only it will be like this for me, to gather sheaves into my house — and if only I could bring one, I would rejoice in it”; and hence it was from God’s kindnesses towards all creatures, may God be blessed, to fulfil this desire of theirs when it occurs that the owner of the field forgets it. There is also a benefit for the owner of the field, that he acquires through this a goodly soul; for truly through the trait of generosity and a blessed soul that does not place its heart upon the forgotten sheaf and leaves it to the destitute — on those with such a soul — does the blessing of God descend forever. (Sefer haChinuch 592:1-2)

I have to say I like the idea of it being a mitzvah to forget. While this is based on a blessing to those who even inadvertently support the poor and needy in society, the idea of it being not only a good thing for others but also for ourselves that we can forget something we have held on to closely, is one I can get behind.
How many times have we found ourselves remembering with shame and embarrassment something that happened a long time ago, or that was minor in the minds of everyone else, but stays with us in full technicolour horror down the years? How many times have we hung on to our anger at the actions of someone else?
This is a strange mitzvah in so many ways, because it cannot be done with forethought. But also, it is a mitzvah that can only be done when we have made a mistake, not completed the full task we expected to do or done something not according to plan. We have made a mistake, and we can turn it into a blessing.
So as you examine your lives, look to see what you are holding on to that is holding you back, damaging you in some way or damaging a relationship or a reconciliation. And, recognising that that holding on has been a mistake, practise the idea of turning it into a blessing, let go and forget, it can be over and we can move forward without holding on to emotions that can only damage us.