Abstain

means,

To hold yourself back from;
To keep yourself from.
('Abstain' is a word used
mainly when talking about
the passions, appetites,
or sinful indulgences.)

For this is the will of God,
even your sanctification,
that you should abstain from fornication;
that every one of you should know
how to possess his vessel
in sanctification and honour;
not in the lust of concupiscence,
even as the Gentiles which
know not God.

1 Thessalonians 4:3-5