Tax Question - Liquidating Index Fund to Make Down Payment

[Jesse Smith]

Hopefully a tax professional can offer some perspective on this one.  

We are selling our primary residence and purchasing a new primary residence.  Unfortunately, or current residence has not yet sold.  Therefore, we will be liquidating shares of our Vanguard index funds (held in a general brokerage account) to make the down payment.  When our primary residence sells, we will use the proceeds to re-buy the index funds.

My question - I will be liquidating $65,000 from VTSAX and re-buying the same amount at some point during this year (once we get the funds from our home sale.)  Will I have to pay the capital gains tax on the $65,000 that I sell, or will my re-buy offset that sale?  

Thanks.