§ 2. Ven. Ananda: “This word, ‘becoming, becoming’—to what extent
is there becoming?”
The Buddha: “If there were no kamma ripening in the sensuality property, would sensuality-becoming be discerned?”
Ven. Ananda: “No, lord.”
The Buddha: “Thus kamma is the field, consciousness the seed, and
craving the moisture. The consciousness of living beings hindered by
ignorance & fettered by craving is established in/tuned to a lower
property. Thus there is the production of renewed becoming in the future.
“If there were no kamma ripening in the form-property, would form becoming be discerned?”
Ven. Ananda: “No, lord.”
The Buddha: “Thus kamma is the field, consciousness the seed, and
craving the moisture. The consciousness of living beings hindered by
ignorance & fettered by craving is established in/tuned to a middling property. Thus there is the production of renewed becoming in the future.
“If there were no kamma ripening in the formless-property, would
formless-becoming be discerned?”
Ven. Ananda: “No, lord.”
The Buddha: “Thus kamma is the field, consciousness the seed, and
craving the moisture. The consciousness of living beings hindered by
ignorance & fettered by craving is established in/tuned to a refined property. Thus there is the production of renewed becoming in the future.
This is how there is becoming.” — AN 3:76
.............................
§ 7. “Where there is no passion for the nutriment of physical food,
where there is no delight, no craving, then consciousness does not land
there or grow. Where consciousness does not land or grow, name-&-form does not alight. Where name-&-form does not alight, there is no growth of fabrications. Where there is no growth of fabrications, there is no production of renewed becoming in the future. Where there is no production of renewed becoming in the future, there is no future birth, aging, & death. That, I tell you, has no sorrow, affliction, or despair. [Similarly with the nutriment of contact, intellectual intention, and consciousness.] - SN 12:64
As that outline shows, becoming constitutes a sense of self-identity located in a particular world. The contours of that self and that world are determined by a combination of old kamma and new; their location is determined by an act of craving and desire.