We read in Acts of the early church casting lots in order to determine the will of God. Proverbs 16:33 tells us: "The lot is cast into the lap,but its every decision is from the Lord." The question then arises: "Why do we not cast lots today to determine the Lord's will?"
Let me first answer the question whether Christians should cast lots today or not with a clear "no." Why not? I believe the answer lies within the time period of Acts 1:12-26. First, it is important to note that the early church cast lots before the giving of the Holy Spirit at Pentecost. Second, we do not read of the early church ever casting lots after Pentecost. Why? Because the Holy Spirit indwells believers and guides them in decision making.
What then should we do to seek God's will? First, we should look to the scripture. Many questions can be decided by simply knowing what God has directed us to do in scripture. Second, we should pray in the Holy Spirit (Jude 1:20). Romans 8:26-27 tells us: "26 Likewise the Spirit helps us in our weakness. For we do not know what to pray for as we ought, but the Spirit himself intercedes for us with groanings too deep for words. 27 And he who searches hearts knows what is the mind of the Spirit, because the Spirit intercedes for the saints according to the will of God. 28 And we know that for those who love God all things work together for good, for those who are called according to his purpose. " In John 16:13 Jesus tells His disciples of the promise of the Spirit: "When the Spirit of truth comes, he will guide you into all the truth, for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come."
Having received the gift of the Holy Spirit, Christians today, then have no need for casting lots.