Because they have forsaken me, and have estranged this place, and have burned incense in it unto other gods, whom neither they nor their fathers have known, nor the kings of Judah, and have filled this place with the blood of innocents;
They have forsaken me - (Isaiah 65:11).
Estranged this place - devoted it to the worship of strange gods; alienating a portion of the sacred city from God, the rightful Lord of the temple, city, and whole land.
Gods whom ... nor their fathers have known - namely, the godly among their fathers; their ungodly fathers God makes no account of.
Blood of innocents - slain in honour of Moloch (Jeremiah 7:31; Psalms 106:37).