In the US Constitution:
Article 6: no religious test shall ever be required as a qualification to any office or public trust under the United States.
First Amendment: Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof
In the Texas Constitution:
Sec. 4. RELIGIOUS TESTS. No religious test shall ever be required as a qualification to any office, or public trust, in this State; nor shall any one be excluded from holding office on account of his religious sentiments, provided he acknowledge the existence of a Supreme Being.
Sec. 5. WITNESSES NOT DISQUALIFIED BY RELIGIOUS BELIEFS; OATHS AND AFFIRMATIONS. No person shall be disqualified to give evidence in any of the Courts of this State on account of his religious opinions, or for the want of any religious belief, but all oaths or affirmations shall be administered in the mode most binding upon the conscience, and shall be taken subject to the pains and penalties of perjury.
Sec. 6. FREEDOM OF WORSHIP. All men have a natural and indefeasible right to worship Almighty God according to the dictates of their own consciences. No man shall be compelled to attend, erect or support any place of worship, or to maintain any ministry against his consent. No human authority ought, in any case whatever, to control or interfere with the rights of conscience in matters of religion, and no preference shall ever be given by law to any religious society or mode of worship. But it shall be the duty of the Legislature to pass such laws as may be necessary to protect equally every religious denomination in the peaceable enjoyment of its own mode of public worship.
Sec. 7. APPROPRIATIONS FOR SECTARIAN PURPOSES. No money shall be appropriated, or drawn from the Treasury for the benefit of any sect, or religious society, theological or religious seminary; nor shall property belonging to the State be appropriated for any such purposes.
