The main focus of this research illuminates the meaning of generativity especially in post- modern ecological crisis era. For this, the researcher is challenged to find out the authentic experience of midlife christian adults’ nature experience and to reconstruct for the generativity concept in ecological context including God, human, and nature. The phenomenological approach and metaphor theological method are employed for the analysis of midlife adults’real experiences as for the research design and methods. Through theological reflection, this study reaches conclusion as follows: First, there are two drives of the contextual system of nature experience. One of them is the inner drive and the other one is the outer motivation. Second, the authentic experiences of nature experience are ‘modify of the God-world relational model’and ‘the recovery in the modified relational model’. Third, the process of nature experience of midlife is very expansive one. These empirical and understanding expansion bring about practical attitude which is good for sang saeng community. Fourth, The participants of midlife look for the new generativity concept through nature experience. Researcher named the new generativity concept from paticipants‘ Ecological generativity’. Last, the metarphor method is used for theological discussion. Researcher proposed the sang saeng model, a conductor metarphor and an orchestra metarphor acording to participants’empirical data. And Researcher named concrete life style in sangsaeng model as ecological generativity. Futhermore, the alternative pastoral counseling provides concrete method to expand experience, recognition, practical action of sangsaeng relationship.