I've recently been reflecting on the use of concentration practice to generate positive mind-states that stick around to support insight practice. Normally, I'd think about this just in terms of jhana numbers (1,2,3, etc). However, recent experiementation is showing that there's a lot more too it than that. The quality of the jhana object formed in access concentration can vary widely, and it seems to me that the quality of the access concentration object matters just as much or possibly more than the jhana number of hardness of the jhana when considering the positive residual effects of the mind state.
For example, with metta there are numerous variables that go into the strength and breadth of the object.
Just a few:
How many different beings one practised metta toward?
How many different categories of friend, neutral, enemy, etc?
How many different multi-person classes?
How many different directions was the metta sent in?
How strongly was boundlessness established in each direction?
Then you could cross multiply all these considerations with how much jhana time/depth was spent with each sub-object (e.g., 3 minutes in a medium-hard 2nd jhana toward a friend in the upwards direction.) Lately, I've taken the time to try to really develop the metta-field rigorously by doing jhanas on multiple beings from multiple categories in 14 directions (plus the centre, making 15 total). Then extending the field outward until it becomes boundless in all 14 directions (I use the sides of a cub-octahedron to visualize the 14 directions). I can report that the post samatha practice quality of this metta-field was extremely strong in comparison to previous attempts where I've tended to just pick a single object and spend a long time developing as hard a 3rd jhana as I can on that one object. Using the multi-object strategy, I just spend a minute or 2 in fairly soft 1st jhanas on each object, but the resultant mind-state was much more powerful than the stronger jhana on a single object.
What do I mean by the post-samatha quality of the metta-field. I mean that in practising vipassana afterwards there is a rock-solid bullet proof feeling of utter safety and ease. Shit can be going crazy through dissolutions, wild vibrations, and emotional upheavals all over the place, but my attention can stay with them and stay with the practice without disturbance. In addition, there is a profound healing quality to the field such that after the period of insight practice, I feel utterly centred and peaceful and emotionally satisfied rather than frazzled by the hell I've just gone through.
Tonight, I tried setting up a field using the quality of bhakti/devotion. This is not a quality that is often talked about on this board, or by secular Buddhists generally, but in the Mahayana and Vajrayana traditions, devotion is quite commonly used. Devotion is basically the kind of profound love that a parent has towards a child or that a person has for their beloved spouse. It's a completely different type of love than metta. Metta is universal and can therefore arise in response to any being, whereas devotion arises only in response to beings with which one has established a special devotional relationship. Most religious traditions rely heavily on devotion to generate states of concentration. If you look at Western religions, they don't have much in the way of formal concentration technique, but mystics in these traditions are able to achieve profound mystical states simply through the continuity of devotional practice. The reason is that devotion naturally concentrates the mind (I was recently told by a reputed source that this principle is a major foundation of practice in the Shingon school of Vajrayana).
So to get on with my point, I used my usual prayer/mantras and visualization to establish the quality of devotion and ran through 1st to 3rd jhana on it. Then I returned to access concentration and generated it in 6 directions and then expanded the field out to boundlessness. Once the field stabilized, I re-entered jhana on a little spot in the field and this felt significantly harder and more powerful than the first time around. Then I exited jhana and began practising vipassana.
This was the best support for the practice I've managed to generate so far. I felt like a my mind was about 3 or 4 times as fast as normal for noticing sensations and I just effortlessly moved through really atrociously bad dukka states as if they were a walk in the park. The afterglow of the state lasted for several hours.
The long and the short of it is I highly recommend using supportive positive mind-state fields for vipassina practice. I'd love to hear if anybody else has had good results with this, or if there are any combination of mind-state fields that work particularly well for you. Also, I'd welcome more general discussion of the much greater complexity of concentration strength that is acknowledged by jhana numbers + degree of hardness.
Avi Craimer