Dear Brothers and Sisters,
Faith is an indispensable part of our lives which we may overlook sometimes. When an infant takes his or her steps it is on faith that it can walk. Seeing those around walking believes that it is possible. When an army engages in war it is because they believe they can overcome or achieve their intended goal by engaging an enemy. Without faith, in what they want to achieve, they do not engage the enemy, they surrender. When Apostle Peter was commanded to walk on the water of the lake he was able to do it as long as he believed; by having all his attention fixed on the Lord he “knew” he could do it. But the moment his faith decreased by losing his focus and being influenced by the powerful wind and the waves it created he started to sink. (Mat. 14:29)
So, the Apostles knew that in order to be able to apply these new commandments of the Lord they needed more faith. To which our Lord agrees and He tells them that they actually require only a small amount of faith, like the size of the mustard seed; BUT this faith has to be fervent, burning hot, like the mustard seed. With such faith they can move mountains. Of course our Lord does not mean literal mountains (although He can if in similar or equivalent situations, for example Prophet Moses parting the Red Sea). What he means is that when someone sins against us and our heart hurts and becomes heavy as if a large boulder has been placed on it. our fervent faith can overcome it. Even if it feels that, that hurt is like a mountain weighing on our hearts with fervent faith in our Lord and knowing that He will take care of all things we can cast that mountain into the sea and to never see it again.
But our Lord warns us that when we do forgive our repentant brother or sister who sinned against us we should be humble and give all glory to God, lest we fall into pride.
May our Lord grant us such a fervent faith, even if it is as small as a mustard seed to forgive our repentant brother and sister and make us worthy to inherit His Kingdom. Amen.