What is the meaning of Mark 11:22-24?

22 And Jesus answering saith unto them, Have faith in God. 23 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. 24 Therefore I say unto you, What things soever ye desire, when ye pray, believe that ye receive them, and ye shall have them. Mark 11:22-24

Thomas Scott

(Mt 21:18-22.) The apostles were exhorted to have “faith in God,” or “the faith of God;” that is, a firm confidence in his power and truth, as enabling them to effect those things which they undertook in his name. This was peculiarly applicable to the exercise of faith required in working miracles. ‘These were generally introduced by some solemn declaration of what was intended, which was in effect a prediction of immediate success. So Peter says (Ac 3:8), “In the name of Jesus Christ, rise up and walk;” and (Mr 9:34) “Eneas, Jesus Christ maketh thee whole.” And in pronouncing this, the person speaking pawned all his credit as a messenger from God, and consequently all the honor and usefulness of his future life, on the immediate miraculous powers were given.’—Doddridge. Such exhortations, however, should also be regarded in all our expectations and prayers, grounded on the promises of God, which will certainly be fulfilled to every believer in the proper meaning of them, and in the due season; and this we should expect, notwithstanding difficulties and apparent improbabilities. Therefore, whatever we desire, when we pray, we should confidently hope to receive, and go on with our duty as though we had received it. But if we would thus have confidence in prayer before a holy God, we must have an assured hope of his merciful forgiveness; in order to which, we must fully and heartily forgive all that have injured us. (Mt 6:12,14,15; 18:21-35.)