I’ve heard some Christians say, “Sometimes, we have to be selfish and take care of ourselves.” While I understand the intention, I do not agree with the premise. There is NO time that a Christian should be selfish. 
“Let no on seek his own good, but the good of his neighbor.” 1 Cor. 10:24And this means that we even limit our freedom for the sake of others! Paul said this in the context of answering questions about whether eating meat offered to an idol is allowed for Christians. Paul says that although it is allowed (since meat is meat), if it will hurt a weaker Christian’s conscience, then we should refrain from it even though we have every right to eat it. 
This means if my watching an R-rated movie will make some church members doubt my spirituality, then I will refrain from it. In other words, I will not do what I know I have the right to do if it will hurt a fellow brother/sister. 
Does that mean that we never take a rest and only cater to other people’s needs 24-7? No. We do take a rest. But when we do, we are not doing it for our sake. We are doing it so that we can be well-rested to serve others better. 
So then isn’t it just semantics that we say sometimes we need to be selfish and care take of ourselves, so that we can take care of others better? Perhaps. But I worry that when we give ourselves the okay to be selfish (for whatever reason), we never get to the “so that we can serve others better…” 
Live for others! All the time!
PH