WLC Q.181: Why are we to pray in the name of Christ?
The sinfulness of man, and his distance from God by reason thereof, being so great, as that we can have no access into his presence without a mediator; (John 14:6, Isa. 59:2, Eph. 3:12) and there being none in heaven or earth appointed to, or fit for, that glorious work but Christ alone, (John 6;27, Heb. 7:25–27, 1 Tim. 2:5) we are to pray in no other name but his only. (Col. 3:17, Heb. 13:15)