It is considered criminal to teach vajrayana, or tantric Buddhism, by presenting it as ordinary. Students should first be taught hinayana and mahayana, the earlier teachings, and only then should they be shown the path of vajrayana. There needs to be immense respect for the hinayana practice of meditation, or shamatha-vipashyana, and for the practice of the bodhisattva, the mahayana practitioner, both in terms of developing good conduct and also having a glimpse of shunyata or emptiness. Having had that training, the worthy person can then enter into the next stage properly, the vajrayana.
From “Unconditional Ground” in, The Tantric Path of Indestructible Wakefulness, Volume Three of The Profound Treasury of the Ocean of Dharma, by Chögyam Trungpa, page 261.