Genesis 15:5-6 (ESV)
"Look toward heaven, and number the stars, if you are able to number them." ... "So shall your offspring be."
And he believed the Lord, and he counted it to him as righteousness.
Abraham's Oak, 1905
Henry Ossawa Tanner (American, 1859-1937)
The tree depicted is known as the Oak of Mamre, which in some traditions marks where Abraham pitched his tent.