Complex sentence: The Buddha himself entered "jhāna", as described in the early texts, during his own quest for enlightenment, and is constantly seen in the "suttas" encouraging his disciples to develop "jhāna" as a way of achieving awakening and liberation.
Split into simpler sentences: The Buddha himself entered "jhāna", as described in the early texts, during his own quest for enlightenment. In the "suttas" the Buddha is depicted many times encouraging his disciples to develop "jhāna" as a way of achieving awakening and liberation.