Bede the Venerable
Catena Aurea · Markusevangelium 11
And when even was come, he went out of the city. And in the morning, as they passed by, they saw the fig tree dried up from the roots. And Peter calling to remembrance saith unto him, Master, behold, the fig tree which thou cursedst is withered away. And Jesus answering saith unto them, Have faith in God. For verily I say unto you, That whosoever shall say unto this mountain, Be thou removed, and be thou cast into the sea; and shall not doubt in his heart, but shall believe that those things which he saith shall come to pass; he shall have whatsoever he saith. Therefore I say unto you, What things soever ye desire, when ye pray, believe that ye receive them, and ye shall have them. And when ye stand praying, forgive, if ye have ought against any: that your Father also which is in heaven may forgive you your trespasses. But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses.
(ubi sup.) But we must observe that there is a difference in those who pray; he who has perfect faith, which worketh by love, can by his prayer or even his command remove spiritual mountains, as Paul did with Elymas the sorcerer. But let those who are unable to mount up to such a height1 of perfection pray that their sins should be forgiven them, and they shall obtain what they pray for, provided that they themselves first forgive those who have sinned against them. If however they disdain to do this, not only shall they be unable to perform miracles by their prayers, but they shall not even be able to obtain pardon for their sins, which is implied in what follows; But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses.