Seekers should ask questions, read books, remain skeptical, use intuition and common sense, and run like crazy if a teacher asks for money or sex.
Some sages are thinkers and can clearly explain what's going on and how to escape illusions created by thought, but others are feelers and teach more intuitively. One good indicator of clarity is a teacher's sense of humor and whether s/he can laugh at him/herself.
The best teachers tell seekers to look within themselves and not to depend upon any outside sources because they know that all answers to all questions are contained within the seeker. They constantly point away from imagination to the aliveness of being. They constantly cut the ground out from under seekers, and leave them with nothing ideationally solid to stand on.
Some sages are thinkers and can clearly explain what's going on and how to escape illusions created by thought, but others are feelers and teach more intuitively. One good indicator of clarity is a teacher's sense of humor and whether s/he can laugh at him/herself.
The best teachers tell seekers to look within themselves and not to depend upon any outside sources because they know that all answers to all questions are contained within the seeker. They constantly point away from imagination to the aliveness of being. They constantly cut the ground out from under seekers, and leave them with nothing ideationally solid to stand on.