Did the messengers call people to the oneness of lordship?

The questioner:
Honorable Shaykh, may Allah grant you success. This questioner says: Imam Ibn al-Qayyim (may Allah have mercy on him) mentioned that the tawhid (the oneness of Allah) to which the messengers called and by which the books were sent is of two types: tawhid in knowledge and affirmation, and tawhid in seeking and intention. He asks: Does this mean that the messengers...

The Shaykh:
...in knowledge and affirmation, this is tawhid al-rububiyyah (oneness of lordship), and seeking and intention, this is tawhid al-uluhiyyah (oneness of worship). Yes.

The questioner:
Then he says, may Allah preserve you: Does this mean that the messengers also called to tawhid al-rububiyyah (oneness of lordship)?

The Shaykh:
Yes, it is used as evidence for tawhid al-uluhiyyah (oneness of worship). Tawhid al-rububiyyah (oneness of lordship) is used as evidence for tawhid al-uluhiyyah (oneness of worship). Yes.