Joy shall be in heaven over one sinner that repenteth, more than over ninety and nine just persons, which need no repentance.
It may seem foolish for the shepherd to leave the 99 sheep to go search for just the one. But the shepherd knew that the 99 would be safe in the sheepfold, whereas the lost sheep was in danger. Because each sheep was of high value, the shepherd knew it was worthwhile to search diligently for the lost one. God's love for each individual is so great that he seeks each one out and rejoices when he or she is "found". Jesus associated with sinners because he wanted to bring the lost sheep - people considered beyond hope - the Gospel of God's Kingdom. Before you were a believer he sought you, and his love is still seeking those who are yet lost.