Buddhist-Meditation-Systematic-and-Practical

form only may be taken as yidam. That many forms
may have the same name does not mean that they are all
the same in practice. For instance, of the bodhisattva
Tara there are twenty-one forms and each possesses
quite a different mantra. Once a peaceful or a wrathful
form is chosen as yidam, one must only worship that
one as the yidam. One may also practice other forms of
the same deity, but these cannot be the yidam.
A meditator may have the same yidam throughout all
four initiations of anuttarayoga. In the lower three yogas
there is only a method of offering to one particular
Buddha (etc.) who is "outside" oneself; this differs from
the highest yoga where oneself becomes the yidam.
Although these two may seem similar, in fact, the yidam
only appears in the first initiation of the fourth yoga,
and Tibetan works never talk about yidam in the lower
three yogas where there is just devotion to one
particular spiritual figure.
Some of these deities have no heruka-form and such is
Green Tara. If she is one's yidam, it is good for the first
initiation and she may again be worshiped in single
form in the fourth initiation; but in the third, the yidam
must be in heruka-form. Of course, there is no reason
why Green Tara should not be seen with a partner and if
one is really skilled in meditation, she might be seen in
this way, though traditionally she is single. In this case
another form of Tara may be practiced in the Third
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