Arahatship is a spiritual attainment, perhaps the “biggest” and best that there is.
This attainment is the end of dukkha.
It seems to be the attainment of an unconditional state of happiness beyond dukkha.
Compassion is the wish or desire for the decrease of dukkha for oneself, others, or both oneself and others.
Thus, the desire for spiritual attainments that the Buddha himself taught were worth attaining, might be chanda or piha as mentioned by Venerable Brahmali:
or even some form of compassion: looking for way out of dukkha through spiritual attainments up to and including Arahantship.
The idea of “craving for spiritual attainments” being a “fetter” seems to be a relatively misguided one that does not have a firm and solid basis in the EBT’s.
These three kinds of people are found in the world.
What three?
The hopeless, the hopeful, and the one who has done away with hope.And what, mendicants, is a hopeless person?
It never occurs to them: ‘Oh, when will the aristocrats anoint me too as king?’ This is called a hopeless person.And what, mendicants, is a hopeful person?
It occurs to him: ‘Oh, when will the aristocrats anoint me too as king?’ This is called a hopeful person.And what, mendicants, is a person who has done away with hope?
It never occurs to him: ‘Oh, when will the aristocrats anoint me too as king?’ Why is that? Because the former hope he had to be anointed has now died down. This is called a person who has done away with hope.…And what, mendicants, is a person who has done away with hope? It’s when a mendicant is a perfected one, who has ended all defilements. They hear this: ‘They say that the mendicant named so-and-so has realized the undefiled freedom of heart and freedom by wisdom in this very life. And they live having realized it with their own insight due to the ending of defilements.’ It never occurs to them: ‘Oh, when will I too realize the undefiled freedom of heart and freedom by wisdom in this very life, and live having realized it with my own insight due to the ending of defilements.’ Why is that? Because the former hope they had to be freed has now died down. This is called a person who has done away with hope.
-AN 3.13
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