Do not dwell on the past. See I am doing a new thing! Isaiah 43:18-19
When God determines your future, He doesn't consult your past. Mary Magdalene was a known prostitute. But after Christ redeemed her she became one of the last people to leave the cross (See Matthew 27:55-61) and one of the first to discover and announce His resurrection (See Matthew 28:7). Because she embraced Christ and the future He offers all of us, she's been mentioned with honour by every ensuing generation. Peter was a fisherman with a hair-trigger temper and some anti-social tendencies. Yet God filled him with so much spiritual power that when he preached, multitudes came to Christ (See Acts 2:40-41). Rahab was a prostitute who was saved from death because she hid the spies sent by Joshua (Judges 6 25). Jacob lived up to his name 'deceiver' but God gave him an extreme makeover and changed his name to Israel, which means, 'A Prince with God' (See Genesis 32:24-30).
Ruth was a Moabitess who grew up worshipping idols; not a promising start. But after turning to serve the true God, she became part of the ancestry of King David and our Lord Jesus (See Matthew 1:5). Zacchaeus, a well known embezzler, hosted Jesus overnight in his home and ended up becoming a philanthropist. And how about Paul? Killing Christians didn't put him off limits to God. As an apostle he wrote over half of the New Testament by divine revelation, was taken into heaven where he saw incredible things (See 2 Corinthians 12:1-4), and when aprons and handkerchiefs taken from his body were placed on the sick they were healed (See Acts 19:11-12). Now, if God could do all that for 'people with a past,' He can give you a new beginning too!