(1) باب وَقْتِهَا
Al-Bara' reported Allah's Messenger (ﷺ) having said:
He who observes prayer like our prayer and turns his face towards our Qibla (in prayer) and who offers sacrifices (of animals) as we do, he must not slaughter the (animal as a sacrifice) until he has completed the prayer. Thereupon my maternal uncle said: Messenger of Allah, I have sacrificed the animal on behalf of my son. The Messenger of Allah (ﷺ) said: This is the thing in which you have made haste for your family. He said: I have a goat with me better than two goats. Thereupon he said: Sacrifice it for that is the best.
Reference: Sahih Muslim 1961 d
In-book reference: Book 35, Hadith 9
USC-MSA web (English) reference(deprecated numbering scheme): Book 22, Hadith 4826