'Opportunity' in the Bible

For you, my brothers, were called to freedom; only do not let your freedom become an opportunity for the sinful nature (worldliness, selfishness), but through love serve and seek the best for one another.

So then, while we [as individual believers] have the opportunity, let us do good to all people [not only being helpful, but also doing that which promotes their spiritual well-being], and especially [be a blessing] to those of the household of faith (born-again believers).