There are many reasons to pray and we are to pray without ceasing, but in some situations we pray for things that God has already answered. Probably the most prayed-for thing that we seek with the wrong intentions is God’s will. That doesn’t mean we shouldn’t seek His will, just that sometimes we already know it and pray anyway, hoping God will change His mind or even His character.
The best place to find God’s will for us is in the Bible. There are many things for which we seek answers that have already been answered in God’s Word. Before praying for God’s will concerning the relationship you’re about to enter with a married person, consider that He has already spoken on this matter (Exodus 20:14). The same can be said of many decisions we face.
That all being said, if the will of God really is in question and isn’t quite clear, of course prayer should be our first action. It’s never a bad thing to talk to the Lord before making a decision. Just make sure you’re not asking Him to bend to your will rather than truly seeking His.