Yoga sutra iv.3 “nimittam aprayojakam prakrtinam varanabhedah tu tatah ksetrikavat”
“Nature’s efficient cause does not impel its potentialities into action, but helps to remove obstacles to evolution, just as a farmer builds banks to irrigate his fields”.
The sutra is explaining that just because a student of yoga has reaped benefits in their current life through their past actions, i.e.( karma created from a previous life) and was either born with or has easily obtained an understanding of the sutras and therefore the path to kaivalya, freedom, this alone is not enough to transform the sadhaka or for them to obtain kaivalya. But because the sadhaka has this knowledge and knows what will be gained by utilizing it to the fullest, the path to freedom should be easier to follow than someone who is without this knowledge.
Where others may only see the cycle of life and death and be filled with joy and grief, the sadhaka will be able to understand that the cycle is natures way of showing constant change. The sadhaka will understand that we have no control over anything outside of ourselves and therefore must learn to control ourselves to live within nature.
Therefore by using nature and the natural flow of the earth and it’s creatures the sadhaka will be able to identify obstacles to transformation and use this understanding to remove or overcome obstacles or personal tendencies that hinder their evolution and growth.
The sadhaka will also understand how yogic techniques such as asana, pranayama, and meditation will lead them to the path of samadhi and therefore kaivalya and freedom from the sufferings of this life.