'Begotten' in the Bible

For unto which of the angels said he at any time, Thou art my Son, This day have I begotten thee? and again, I will be to him a Father, And he shall be to me a Son?

So Christ also glorified not himself to be made a high priest, but he that spake unto him, Thou art my Son, This day have I begotten thee:

By faith Abraham, being tried, offered up Isaac: yea, he that had gladly received the promises was offering up his only begotten'son ;