What are the "words" by which God tested Abraham in the āyah? What is meant by "he completed them"?

Imām Ibn al-Jawzī (d. 597/1201) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1. They are five instructions for the head and five for the body. The instructions for the head are: parting the hair , rinsing the mouth, sniffing water into the nose, trimming the moustache, and using a tooth stick (siwāk). The instructions for the body are: clipping the nails, shaving the pubic area, plucking the armpit hair, cleaning oneself with water after using the toilet, and circumcision. [Ṭāwūs from Ibn ʿAbbās]
2. They are ten practices: six related to the person himself and four related to rituals. The personal practices are: shaving the pubic area, plucking the armpit hair, clipping the nails, trimming the mustache, using a tooth stick, bathing after major ritual impurity (janābah), and bathing on Fridays. The ritual practices are: circumambulating the Kaʿbah (ṭawāf), running between Ṣafā and Marwah (saʿy), stoning of the pillars at Mina (ramy al-jamarāt), and performing the ritual slaughtering. [Ḥanash ibn ʿAbd Allāh from Ibn ʿAbbās]
3. They refer to the rites of pilgrimage (manāsik). [Qatādah from Ibn ʿAbbās]
4. It refers to testing him by the star, the sun, the moon, migration, the fire, the sacrifice of his son, and circumcision. [Al-Ḥasan]
5. It refers to every supplication in the Qurʾān, such as “Our Lord, make this a secure city” (14:35) and its like. [Muqātil]

For those who say that "kalimāt" refers to actions that Ibrāhīm performed, the meaning of "so he completed them" is that Ibrāhīm acted upon them. For those who say that "kalimāt" refers to supplications and requests, the meaning of "so He completed them" is that Allah responded to them and fulfilled them.