The so-called 'nature / nurture' debate tends to be less polarised than it used to be and the consensus amongst respected experts in this field is that there are likely to be a number of different influencing factors. It's not been scientifically proven that people are 'born gay' (indeed evidence from identical twin studies suggests that people's sexual attractions are not hard-wired by DNA). There is, however, growing acceptance that biological, including genetic, factors may well play a part in an individual developing same-sex attractions.
Other possible factors include environmental influences (including upbringing, childhood experiences) and relational influences (within the family and / or peer group). Some people stress that the quality of an individual's relationship with their same-sex parent can be a major contributing factor. It has to be said, however, that a causal link has never been scientifically proven and many people who experience same-sex attraction have very strong and healthy relationships with their same-sex parent.
Our view at TfT is that it's best not to be too dogmatic on this issue and to accept that different factors can influence different people in different ways. In a theological sense, we believe that same-sex sexual attractions were never part of God's original plan for creation and are, therefore, (whatever the cause or causes) part of our fallen human nature.
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