When did God choose to save you?
The date of my baptism as an infant. Of course, I have had to cooperate with that grace along the way, and have backslid a couple of times. Some worse than others. We all have the capability of saying "no" to God's grace and salvation (free will), and I pray daily that I don't do or think something that would be saying "no" to Him. I have to trust that His mercy will protect me from myself.