Tread on the threshold - Because the arms, etc., of Dagon were broken off by his fall on the threshold, the threshold became sacred, and neither his priests nor worshippers ever tread on the threshold. Thus it was ordered, in the Divine providence, that, by a religious custom of their own, they should perpetuate their disgrace, the insufficiency of their worship, and the superiority of the God of Israel.
It is supposed that the idolatrous Israelites, in the time of Zephaniah, had adopted the worship of Dagon: and that in this sense 1 Samuel 1:9; is to be understood: In the same day will I punish all those who leap upon the threshold. In order to go into such temples, and not tread on the threshold, the people must step or leap over them; and in this way the above passage may be understood. Indeed, the thresholds of the temples in various places were deemed so sacred that the people were accustomed to fall down and kiss them. When Christianity became corrupted, this adoration of the thresholds of the churches took place.
This custom still existed among the worshippers of Dagon so late as the reign of Josiah (see the marginal reference).