Unlike birthdays or other holidays or similar customs, there are no pagan origins or associations connected to adoptions. And unlike birthday celebrations, the Bible does not put adoption in a bad light.
In the Hebrew Scriptures adoption is not dealt with from the viewpoint of legal procedure, but the basic idea is set forth in several cases such as Abraham and his slave Eliezer (Gen. 15:2-4); Rachel and Leah and the children born to Jacob by their handmaids (Gen. 30:3-8, 12, 13, 24); and Pharaoh's daughter and Moses. (Ex. 2:5-10)
By prudently reflecting on the joyfulness of the event of adopting a child is similar to that of celebrating a wedding anniversary. Consider what the 10/15/98 Watchtower mentioned about wedding anniversaries:
"It thus would not be strange that a couple might on their wedding anniversary take time to reflect on the joyfulness of that event and on their resolve to work for success as a couple. Whether they focus on this happy occasion in private, just as a couple, or they have a few relatives or close friends with them would be for them to decide. The occasion should not become a mere excuse for a large social gathering. On this occasion Christians would want to be guided by the principles that apply every day of their lives. So whether one takes note of a wedding anniversary or not is a personal matter. —Romans 13:13, 14."
For more, see:
ADOPTION - Links to Information (INDEX; Watchtower Online Library)
In the Hebrew Scriptures adoption is not dealt with from the viewpoint of legal procedure, but the basic idea is set forth in several cases such as Abraham and his slave Eliezer (Gen. 15:2-4); Rachel and Leah and the children born to Jacob by their handmaids (Gen. 30:3-8, 12, 13, 24); and Pharaoh's daughter and Moses. (Ex. 2:5-10)
By prudently reflecting on the joyfulness of the event of adopting a child is similar to that of celebrating a wedding anniversary. Consider what the 10/15/98 Watchtower mentioned about wedding anniversaries:
"It thus would not be strange that a couple might on their wedding anniversary take time to reflect on the joyfulness of that event and on their resolve to work for success as a couple. Whether they focus on this happy occasion in private, just as a couple, or they have a few relatives or close friends with them would be for them to decide. The occasion should not become a mere excuse for a large social gathering. On this occasion Christians would want to be guided by the principles that apply every day of their lives. So whether one takes note of a wedding anniversary or not is a personal matter. —Romans 13:13, 14."
For more, see:
ADOPTION - Links to Information (INDEX; Watchtower Online Library)