Exodus 18:7

And Moses went out to meet his father-in-law, and did obeisance, and kissed him, he welcomed him in a manner befitting his station; and they asked each other of their welfare, whether peace in the best sense of the word had been granted them. And they came into the tent. "Notice the delicate discretion which both men observe, with all their friendship towards each other. Jethro does not rush impetuously forward; he sends word of his approach. Moses receives him with appropriate reverence, but first leads him into his tent; for whether and how he may introduce him to his people is yet to be determined. " (Lange.)