To speak for God? To serve God? To baptize a new believer? To preach the Word of God (SCRIPTURE)?

My Bible tells me:

John 1:11-13
11 He came to His own, and His own did not receive Him. 12 But as many as received Him, to them He gave the right to become children of God, to those who believe in His name: 13 who were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.
NKJV

1 Peter 2:7-10
7 Therefore, to you who believe, He is precious; but to those who are disobedient,
"The stone which the builders rejected
Has become the chief cornerstone,"
8 and
"A stone of stumbling
And a rock of offense."
They stumble, being disobedient to the word, to which they also were appointed.
9 But you are a chosen generation, a royal priesthood, a holy nation, His own special people, that you may proclaim the praises of Him who called you out of darkness into His marvelous light; 10 who once were not a people but are now the people of God, who had not obtained mercy but now have obtained mercy.
NKJV


As a BELIEVER I am a member of CHRIST'S ROYAL PRIESTHOOD, and all priests live to serve their master and have the right to do so.

NOBODY has more authority to speak for, act for God that that.

IF you disagree, then SHOW US SCRIPTURE that says we should believe you. . .