From the article linked to in OP:
Qualifying Organizations
You can deduct cash contributions or tithes as long as they're made to a qualifying organization. Section 170 of the Internal Revenue Code specifies several categories of qualifying organizations. The IRS permits deductions for charitable contributions to religious organizations, including churches, a convention or association of churches, temples, mosques, synagogues and other religious organizations. Generally, a church or other religious organization must obtain 501(c)(3) status to qualify as a charitable organization. If you're not sure whether your church or religious organization qualifies, you can visit the IRS website to check an organization's tax-exempt status.
Claiming the Deduction
To claim tithes or church giving on your taxes, you must itemize your deductions using Schedule A and attach this to your 1040 tax form. You cannot deduct any tithes or non-cash donations if you choose the standard deduction. Depending on the amount of your tithes, taking the standard deduction may benefit you more than itemizing. If you plan to deduct more than $250 in tithes, you must obtain an official document from the church attesting to the amount of donations you've made throughout the year. If you tithe by check, you should also keep copies of your bank records in case you become the target of an IRS audit.
Deduction Limits
The IRS imposes a limit on the amount of tithes you can deduct each year. According to IRS Publication 526, the maximum amount of charitable contributions, including tithes, that you can deduct is an amount equal to 50 percent of your adjusted gross income. If, for some reason, you've tithed more than 50 percent of your adjusted gross income to the church in any one year, the IRS allows you to carry over the deduction to future tax years. The IRS allows you to use carry-over deductions for up to five years following the initial charitable contribution.
Non-cash Donations
In addition to deducting tithes, you may be able to deduct the value of any goods or property you donate to the church. The deduction limits and filing rules are the same for non-cash contributions but additional paperwork is required if the value of your donations exceeds $500. In addition to Schedule A, you must complete Form 8283 and attach it to your tax return. You must provide a description of each item donated along with an estimate of its fair market value. If you donate an individual item worth $5,000 or more, you must have the item professionally appraised to verify its value.