The One Hundred and Fifty Verses of Praise says:
Take refuge in whomever
Has absolutely no shortcomings,
Absolutely no blindness, and in whom resides
Every aspect of all good qualities.
When you think of this,
Respect those who praise him
And abide by his teachings.
In other words, when you think of how to distinguish between
what should be your refuge, and what should not, you will want to
take refuge in the Buddha, the teacher of Buddhism, in his
teachings, and in those who abide by his teachings. The average
worldly person seeks refuge in worldly creatures – spirit kings,
gods, nagas, spirits, and so forth. Non-Buddhists seek refuge in
Brahma, Indra etc. but these themselves are beings in samsara so
they are not fitting refuges.
Who then is a fitting refuge?
From The Seventy Verses on Taking Refuge:
Buddha, Dharma, Sangha
Are the refuge for seekers of liberation.
That is, the only refuge is the Three Jewels: Buddha,
Dharma and Sangha. But if we do not identify these three
properly, we will not take refuge purely. We are not critical and
so pretend to be Mahayana knowledge-bearers, yet when things go
wrong, sickness comes and so forth, or when we have some important
work to do, we seek refuge in worldly Dharma protectors, in spirit
kings, local gods etc: we perform smoke purifications or carry wood
talismans under our armpits; we rush off to the shrine of any
deity. All this external activity indicates our inner state.
Buddhists should entrust themselves to the Three Jewels. We may
have actually gained admittance to a Monastery, but we do not even
qualify to be Buddhists, let alone Mahayana knowledge-bearers.
Nagas, spirit kings, and others do not have these three
qualities: omniscience, love and ability. They
don’t even know when they are going to die. Normally they are
categorised as animals or hungry ghosts, and their rebirths are
inferior to ours. There is no worse method we could use than to
rely on them. What means could be worse than to seek refuge in
them? So far from protecting us from samsara and the sufferings of
the lower realms, or even giving us a little temporary help, they
may do us great harm instead. Here is a story to illustrate this. A
man with a goitre once went to a place haunted by flesh-eating
spirits. A tax in flesh that these spirits paid to other creatures
was due, so the spirits removed the man’s goitre. Another man with
a goitre went to them and took refuge in them hoping for the same
result, but the spirits did not destroy his goitre – they made it
larger. Similarly, worldly gods and evil spirits are sometimes
helpful, sometimes harmful; they can never be trusted.
Non-Buddhists make Brahma, Indra, Shiva, and so forth, their
refuge. This is an improvement on the above, yet those gods are
still not liberated from samsara and the lower realms so they
cannot protect other beings. But Buddha, the teacher of Buddhists
is not like these. Praise to the Praiseworthy says:
You proclaimed, ‘I am a
friend
To you who are without protection’.
Your great compassion embraces all beings,
Teacher, you have great compassion,
You have love; you act by your love.
You are diligent, you are not lazy.
Who else could be like you?
You are the protector of all sentient beings;
You are a kind relative to all.
According to that section [the Buddha] has three magnificent
qualities: omniscience, love and ability. Not only do spirit kings,
evil spirits and so forth not have even a portion of these good
qualities, but also the sum of the good qualities of worldly
refuges, gods, nagas, and the like, cannot rival even the good
qualities of a single Shravaka Stream Enterer.
Buddha is the ultimate refuge because he has taken the two
benefits [benefit for self and for others] to their most developed
state. Our teacher has eliminated all faults and possesses all good
qualities.
Simply put, the ultimate jewel of Buddha is assumed to be the
two dharmakayas, or ‘truth bodies’; the relative jewel of Buddha,
the two physical kayas [the sambhogakaya, or 'enjoyment body', and
nirmanakaya, or 'emanation body'].
The jewel of Dharma is as follows. The ultimate jewel of Dharma
is anything that comes under the truth of cessation or the truth of
the path – these are the [two] purifying truths [in contrast to the
two truths of suffering and the origin of suffering] in the
mind-streams of Aryas. As a guide, we take the ‘truth of cessation’
partly to mean a freedom from [or the 'cessation' of some
particular obscuration, this freedom being a function of a
particular unhindered path. The 'truth of the path' is taken to be
the means for Aryas to achieve these cessations and realisations in
their mindstreams. People who have not studied the classics and who
think at a lower level may instead identify the three scopes of the
Lam Rim as a rough approximation for the ultimate jewel of
Dharma.
Such things as the twelve divisions of Scripture are the
generally accepted idea of the jewel of Dharma.
The jewel of Sangha is as follows. The ultimate jewel of Sangha
are Aryas who have any of the eight good qualities of the liberated
mind.
A group of four ordinary beings holding the monk's full
ordination vows is the generally accepted idea of the jewel of
Sangha. If we help or harm these beings we will receive virtuous or
non-virtuous karmic results in relation to the Sangha.
One doesn't need all three of these refuges in order to be
protected from some types of danger; each of the Three Jewels can
protect one. Once a man in Dokham petitioned Avalokiteshvara while
he was being dragged off by a tiger. The tiger immediately put him
down and the man was freed from all danger.
After Purna became ordained and gained arhatship, some relatives
and merchants went to sea to obtain choice sandalwood, but their
boat began to disintegrate. The relatives petitioned the Arhat
Purna [in their prayers] and were saved from the waters.
The king of nagas caused a rain of weapons to fall on King
Prasenajit; Maudgalyayana turned it into a rain of flowers.
However, all Three Jewels are needed to protect one completely
from samsara and the lower realms. To cure a patient of a severe
illness, three things are needed: a doctor, medicine, and nurses.
Similarly, in order to be freed from the serious illnesses of the
sufferings of samsara and the lower realms, the danger of the peace
[of Hinayana Arhats], or [samsaric] existence, one definitely needs
all these: the Buddha, the teacher of the liberating path, who is
like the doctor; the Dharma, the liberating path of the three
scopes, which is like the medicine; and the Sangha, the friends of
the Dharma practitioners, who are like the nurses. So, these three
are things to take refuge in.