But thou, when thou prayest, enter into thy closet, and when thou hast shut thy door, pray to thy Father which is in secret; and thy Father which seeth in secret shall reward thee openly. Matthew 6:6
Jesus prayed aloud on the cross.
Matthew 27:46 And about the ninth hour Jesus cried with a loud voice, saying, Eli, Eli, lama sabachthani? that is to say, My God, my God, why hast thou forsaken me? 27:47 Some of them that stood there, when they heard that, said, This man calleth for Elias.
He also prayed publicly at the tomb of Lazarus.
John 11:41 Then they took away the stone from the place where the dead was laid. And Jesus lifted up his eyes, and said, Father, I thank thee that thou hast heard me. 11:42 And I knew that thou hearest me always: but because of the people which stand by I said it, that they may believe that thou hast sent me.
What Jesus condemned was ostentatious and pretentious prayers, not loud prayers, or open prayers of public interest.
Royal Flock of Christ Church 