Most Christians are familiar with this scripture.
Let the Children Come to Me
"And they were bringing children to him that he might touch them, and the disciples rebuked them. But when Jesus saw it, he was indignant and said to them, “Let the children come to me; do not hinder them, for to such belongs the kingdom of God. Truly, I say to you, whoever does not receive the kingdom of God like a child shall not enter it.” And he took them in his arms and blessed them, laying his hands on them."
Even though this is reporting an experience of Jeremiah, I believe it is also a demonstration of when the Lord begins participation in the lives of all humans.
The Call of Jeremiah
"Now the word of the LORD came to me, saying,
“Before I formed you in the womb I knew you,
and before you were born I consecrated you;
I appointed you a prophet to the nations.”"
I believe there are three essential elements required for the birth of a child. 1. the egg, 2. the sperm, and 3. God's law. Once the fertilization process occurs, the resulting zygote deserves the protection of more of God's law, specifically that of "You shall not Murder".