Two reasons I am a Calvinist:

“When the Gentiles heard this, they began rejoicing and glorifying the word of the Lord; and as many as had been appointed to eternal life believed.” (Acts 13:48)  

“A woman named Lydia, from the city of Thyatira, a seller of purple fabrics, a worshiper of God, was listening: and the Lord opened her heart to respond to the things spoken by Paul.” (Acts 16:14)