In Pureland Buddhism we say that "only nembutsu is real and true" meaning that it is the direct relationship between one's lived life and the Buddha that is the reality. All doctrine, dogma and concept, while sometimes immensely useful, is abstract and so is not actually real. All human knowledge is like this. All science is like this. It is abstract - hugely useful but not "the-thing-itself". All Buddhist wisdom is also like this - the Buddha spoke to, we say, 84000 different groups in his lifetime. Everything he said is abstraction. The reality was the life he lived and the most real aspect of that life was the relationship that his lived-life had to the "Great Lineage" - the Buddhas of past, present and future. This is what he tried to convey through all those teachings. So there is a relationship between the teaching and the thing itself. For this reason, Buddhism has many spiritual exercises. These are means by which one may attain to a more experiential understanding of the Dharma. On the one hand, such spiritual exercises are a way of making the teachings less abstract and more closely related to one's personal life. On the other hand, if the teachings are at one remove from "the-thing-itself" then an exercise to help one understand the teaching is at a second remove. Thus any "means-to-attain" is not "it".
We can see an example of this principle at work in the Contemplation Sutra. There the Buddha meets Queen Vaidehi. Her situation at the time is extremely difficult, imprisoned by her own son. The exchange she has with Gotama is very touching and as a result she is flodded with an experience in which she sees myriads of Buddha Pure Lands and makes a choice for the land of Amida Buddha. This is an over-whelming spiritual ecstacy that she falls into spontaneously through the pressure of her situation and her love for the Buddha. Meanwhile, Ananda who is at hand is deeply impressed by what has happened to the queen and asks how he can have something similar happen. The Buddha then tells him a do-it-by-numbers series of visualisations whereby he can obtain an impression of what the Pure Land of Amida is like. Clearly this is an exercise and equally clearly Ananda is not going to have the fullness of experience that Vaidehi had. We can see here that there is a big gap between an exercise and the thing-itself, between a sadhana and a real encounter with a spiritual being, for instance.
With this caveat, however, there is much to be said for spiritual exercises. They are not the nembutsu itself, but they can deepen our appreciation of the Dharma if we take them in the right way. In this group I will share some spiritual exercises that you can work with if you like. As i say, none of these are essential to Pureland Buddhism - the nembutsu alone is sufficient - but they can help one to understand what the nembutsu is about and they can erode some of the barrier created by our habitual tendency toward abstraction.
Please note that all of these exercises can be considered to be one or another form of either nei quan or chih quan.