Officially opening the £1.5 million Lubavitch Children's Centre in Stamford Hill on Monday, Lord Sacks said he became a rabbi because of the Lubavitch movement.
The Chief Rabbi told more than 150 guests: "In April 1968, I attended the opening of the first Lubavitch building with others and it was the connection made at that wonderful occasion that drew myself and Elaine [Lady Sacks] into the ambit of Chabad Lubavitch. And it changed our lives. I would not be a rabbi, let alone the Chief Rabbi, if Lubavitch did not hold out its hand to me.
"We are as young as our highest priority - our children. The face of the Jewish future is the faces of those beautiful children."
The centre houses a nursery, family services, adult education facilities and the Lubavitch Central Library, stocked with 15,000 books.
Centre manager Rabbi Sholem Sudak said that 500 families had been helped in the six months before the formal opening, way exceeding expectations.
Representing the Hackney Learning Trust, one of the project's backers, Steve Belk said: "This is one of 21 children's centres in Hackney and they have all been set up to help children improve their outcomes, be healthy and make a positive contribution.
"It's really good working in partnership with the Lubavitch Foundation to create a centre for the local community that children and families will take pride in."
To get more from community, click here to sign up for our free community newsletter.