Are infants also to be baptized?

Yes: for since they, as well as the adult, are included in the covenant and church of God; (a) and since redemption from sin (b) by the blood of Christ, and the Holy Ghost, the author of faith, is promised to them no less than to the adult; (c) they must therefore by baptism, as a sign of the covenant, be also admitted into the christian church; and be distinguished from the children of unbelievers (d) as was done in the old covenant or testament by circumcision, (e) instead of which baptism is instituted (f) in the new covenant.

(a) Gen.17:7 And I will establish my covenant between me and thee and thy seed after thee in their generations for an everlasting covenant, to be a God unto thee, and to thy seed after thee. (b) Matt.19:14 But Jesus said, Suffer little children, and forbid them not, to come unto me: for of such is the kingdom of heaven. (c) Luke 1:15 For he shall be great in the sight of the Lord, and shall drink neither wine nor strong drink; and he shall be filled with the Holy Ghost, even from his mother's womb. Ps.22:10 I was cast upon thee from the womb: thou art my God from my mother's belly. Isa.44:1 Yet now hear, O Jacob my servant; and Israel, whom I have chosen: Isa.44:2 Thus saith the LORD that made thee, and formed thee from the womb, which will help thee; Fear not, O Jacob, my servant; and thou, Jesurun, whom I have chosen. Isa.44:3 For I will pour water upon him that is thirsty, and floods upon the dry ground: I will pour my spirit upon thy seed, and my blessing upon thine offspring: Acts 2:39 For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call. (d) Acts 10:47 Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we? (e) Gen.17:14 And the uncircumcised man child whose flesh of his foreskin is not circumcised, that soul shall be cut off from his people; he hath broken my covenant. (f) Col.2:11 In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ: Col.2:12 Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead. Col.2:13 And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses.

Disclaimer: I am only presenting it, not necessarily agreeing with it.